From d81ead8e8310f240422466672594ddc759ed1488 Mon Sep 17 00:00:00 2001
From: Alexandre Gramfort <agramfort@fb.com>
Date: Tue, 4 Apr 2023 13:50:05 +0200
Subject: [PATCH 01/25] WIP : add support for EMG data

---
 mne_bids/config.py | 15 +++++++++++----
 mne_bids/utils.py  |  8 ++++++--
 mne_bids/write.py  |  9 +++++++++
 3 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/mne_bids/config.py b/mne_bids/config.py
index dff8407c82..50707ac7eb 100644
--- a/mne_bids/config.py
+++ b/mne_bids/config.py
@@ -9,7 +9,7 @@
 
 DOI = """https://doi.org/10.21105/joss.01896"""
 
-EPHY_ALLOWED_DATATYPES = ['meg', 'eeg', 'ieeg', 'nirs']
+EPHY_ALLOWED_DATATYPES = ['meg', 'eeg', 'ieeg', 'nirs', 'emg']
 
 ALLOWED_DATATYPES = EPHY_ALLOWED_DATATYPES + ['anat', 'beh']
 
@@ -110,6 +110,9 @@
                           '.set',  # EEGLAB, potentially accompanied by .fdt
                           ]
 
+allowed_extensions_emg = ['.vhdr',  # BrainVision, accompanied by .vmrk, .eeg
+                          ]
+
 allowed_extensions_ieeg = ['.vhdr',  # BrainVision, accompanied by .vmrk, .eeg
                            '.edf',  # European Data Format
                            '.set',  # EEGLAB, potentially accompanied by .fdt
@@ -124,6 +127,7 @@
 ALLOWED_DATATYPE_EXTENSIONS = {
     'meg': allowed_extensions_meg,
     'eeg': allowed_extensions_eeg,
+    'emg': allowed_extensions_emg,
     'ieeg': allowed_extensions_ieeg,
     'nirs': allowed_extensions_nirs
 }
@@ -140,7 +144,7 @@
 # the extension)
 ALLOWED_FILENAME_SUFFIX = [
     'meg', 'markers', 'eeg', 'ieeg', 'T1w', 'FLASH',  # datatype
-    'participants', 'scans',
+    'emg', 'participants', 'scans',
     'electrodes', 'optodes', 'channels', 'coordsystem', 'events',  # sidecars
     'headshape', 'digitizer',  # meg-specific sidecars
     'beh', 'physio', 'stim',  # behavioral
@@ -150,7 +154,7 @@
 # converts suffix to known path modalities
 SUFFIX_TO_DATATYPE = {
     'meg': 'meg', 'headshape': 'meg', 'digitizer': 'meg', 'markers': 'meg',
-    'eeg': 'eeg', 'ieeg': 'ieeg',
+    'eeg': 'eeg', 'ieeg': 'ieeg', 'emg': 'emg',
     'T1w': 'anat', 'FLASH': 'anat'
 }
 
@@ -415,7 +419,10 @@
               'to human intracranial electrophysiology. Scientific Data, '
               '6, 102. https://doi.org/10.1038/s41597-019-0105-7',
               'nirs':
-              'In preperation'}
+              'In preparation',
+              'emg':
+              'In preparation'
+            }
 
 
 # Mapping subject information between MNE-BIDS and MNE-Python.
diff --git a/mne_bids/utils.py b/mne_bids/utils.py
index 9a4a9b2e95..92f108ede2 100644
--- a/mne_bids/utils.py
+++ b/mne_bids/utils.py
@@ -132,17 +132,21 @@ def _handle_datatype(raw, datatype):
             datatypes.append('meg')
         if 'eeg' in raw:
             datatypes.append('eeg')
+        if 'emg' in raw:
+            datatypes.append('emg')
         if 'fnirs_cw_amplitude' in raw:
             datatypes.append('nirs')
         if len(datatypes) == 0:
-            raise ValueError('No MEG, EEG or iEEG channels found in data. '
-                             'Please use raw.set_channel_types to set the '
+            raise ValueError('No MEG, EEG, iEEG or EMG channels found in data.'
+                             ' Please use raw.set_channel_types to set the '
                              'channel types in the data.')
         elif len(datatypes) > 1:
             if 'meg' in datatypes and 'ieeg' not in datatypes:
                 datatype = 'meg'
             elif 'ieeg' in datatypes and 'meg' not in datatypes:
                 datatype = 'ieeg'
+            elif 'emg' in datatypes:
+                datatype = 'emg'
             else:
                 raise ValueError(f'Multiple data types (``{datatypes}``) were '
                                  'found in the data. Please specify the '
diff --git a/mne_bids/write.py b/mne_bids/write.py
index 4df21cbb64..78037b1994 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -883,6 +883,13 @@ def _sidecar_json(raw, task, manufacturer, fname, datatype,
         ('EEGPlacementScheme', _infer_eeg_placement_scheme(raw)),
         ('Manufacturer', manufacturer)]
 
+    ch_info_json_emg = [
+        # ('EEGReference', 'n/a'),
+        # ('EEGGround', 'n/a'),
+        # ('EEGPlacementScheme', _infer_eeg_placement_scheme(raw)),
+        # ('Manufacturer', manufacturer)
+    ]
+
     ch_info_json_ieeg = [
         ('iEEGReference', 'n/a'),
         ('ECOGChannelCount', n_ecogchan),
@@ -912,6 +919,8 @@ def _sidecar_json(raw, task, manufacturer, fname, datatype,
         append_datatype_json = ch_info_json_meg
     elif datatype == 'eeg':
         append_datatype_json = ch_info_json_eeg
+    elif datatype == 'emg':
+        append_datatype_json = ch_info_json_emg
     elif datatype == 'ieeg':
         append_datatype_json = ch_info_json_ieeg
     elif datatype == 'nirs':

From 1e9fde4c55b9aae1853225d3092201513a85b823 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Tue, 8 Oct 2024 13:45:52 -0500
Subject: [PATCH 02/25] fix formatter-mangled comments

---
 mne_bids/config.py | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/mne_bids/config.py b/mne_bids/config.py
index 2e61e23113..7310345326 100644
--- a/mne_bids/config.py
+++ b/mne_bids/config.py
@@ -174,13 +174,16 @@
 # allowed suffixes (i.e. last "_" delimiter in the BIDS filenames before
 # the extension)
 ALLOWED_FILENAME_SUFFIX = [
+    # datatypes:
     "meg",
     "markers",
     "eeg",
     "ieeg",
     "emg",
+    "nirs",
     "T1w",
-    "FLASH",  # datatype
+    "FLASH",
+    # sidecars:
     "participants",
     "scans",
     "sessions",
@@ -188,13 +191,14 @@
     "optodes",
     "channels",
     "coordsystem",
-    "events",  # sidecars
+    "events",
+    # MEG-specific sidecars:
     "headshape",
-    "digitizer",  # meg-specific sidecars
+    "digitizer",
+    # behavioral:
     "beh",
     "physio",
-    "stim",  # behavioral
-    "nirs",
+    "stim",
 ]
 
 # converts suffix to known path modalities
@@ -214,9 +218,9 @@
 ALLOWED_FILENAME_EXTENSIONS = (
     ALLOWED_INPUT_EXTENSIONS
     + [".json", ".tsv", ".tsv.gz", ".nii", ".nii.gz"]
-    + [".pos", ".eeg", ".vmrk"]
-    + [".dat", ".EEG"]  # extra datatype-specific metadata files.
-    + [".mrk"]  # extra eeg extensions  # KIT/Yokogawa/Ricoh marker coil
+    + [".pos", ".eeg", ".vmrk"]  # extra datatype-specific metadata files.
+    + [".dat", ".EEG"]  # extra eeg extensions
+    + [".mrk"]  # KIT/Yokogawa/Ricoh marker coil
 )
 
 # allowed BIDSPath entities

From b3f8b98fc61c8cc67436370efeec841fd4820531 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 9 Oct 2024 17:17:49 -0500
Subject: [PATCH 03/25] add a couple TODOs [ci skip]

---
 mne_bids/config.py | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/mne_bids/config.py b/mne_bids/config.py
index 7310345326..e864ae265f 100644
--- a/mne_bids/config.py
+++ b/mne_bids/config.py
@@ -84,6 +84,8 @@
     ".EEG": "Nihon Kohden",
 }
 
+emg_manufacturers = {}  # TODO
+
 nirs_manufacturers = {".snirf": "SNIRF"}
 
 # file-extension map to mne-python readers
@@ -115,6 +117,7 @@
 MANUFACTURERS = dict()
 MANUFACTURERS.update(meg_manufacturers)
 MANUFACTURERS.update(eeg_manufacturers)
+MANUFACTURERS.update(emg_manufacturers)
 MANUFACTURERS.update(ieeg_manufacturers)
 MANUFACTURERS.update(nirs_manufacturers)
 
@@ -136,7 +139,7 @@
 ]
 
 allowed_extensions_emg = [
-    ".vhdr",  # BrainVision, accompanied by .vmrk, .eeg
+    ".edf",  # European Data Format
 ]
 
 allowed_extensions_ieeg = [
@@ -324,6 +327,7 @@
     + BIDS_EEG_COORDINATE_FRAMES
 )
 ALLOWED_SPACES["ieeg"] = BIDS_SHARED_COORDINATE_FRAMES + BIDS_IEEG_COORDINATE_FRAMES
+ALLOWED_SPACES["emg"] = None  # TODO revise if we support digitization of EMG sensors
 ALLOWED_SPACES["anat"] = None
 ALLOWED_SPACES["beh"] = None
 

From eb4a3f3211abb055b33d51110471b56b010dff8c Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 22 Jan 2025 14:32:29 -0600
Subject: [PATCH 04/25] prevent duplicates

---
 mne_bids/config.py | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)

diff --git a/mne_bids/config.py b/mne_bids/config.py
index 804564b3a2..d984cf350d 100644
--- a/mne_bids/config.py
+++ b/mne_bids/config.py
@@ -166,14 +166,18 @@
 # allow additional extensions that are not BIDS
 # compliant, but we will convert to the
 # recommended formats
-ALLOWED_INPUT_EXTENSIONS = (
-    allowed_extensions_meg
-    + allowed_extensions_eeg
-    + allowed_extensions_ieeg
-    + allowed_extensions_nirs
-    + [".lay", ".EEG", ".cnt", ".CNT", ".bin", ".cdt"]
+ALLOWED_INPUT_EXTENSIONS = sorted(
+    set(
+        allowed_extensions_meg
+        + allowed_extensions_eeg
+        + allowed_extensions_emg
+        + allowed_extensions_ieeg
+        + allowed_extensions_nirs
+        + [".lay", ".EEG", ".cnt", ".CNT", ".bin", ".cdt"]
+    )
 )
 
+
 # allowed suffixes (i.e. last "_" delimiter in the BIDS filenames before
 # the extension)
 ALLOWED_FILENAME_SUFFIX = [

From a0532a86ce06a68e84ef51e23dd9ff9209e9d7cf Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 22 Jan 2025 14:32:56 -0600
Subject: [PATCH 05/25] tweak comment

---
 mne_bids/config.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mne_bids/config.py b/mne_bids/config.py
index d984cf350d..3b94e16c53 100644
--- a/mne_bids/config.py
+++ b/mne_bids/config.py
@@ -331,7 +331,7 @@
     + BIDS_EEG_COORDINATE_FRAMES
 )
 ALLOWED_SPACES["ieeg"] = BIDS_SHARED_COORDINATE_FRAMES + BIDS_IEEG_COORDINATE_FRAMES
-ALLOWED_SPACES["emg"] = None  # TODO revise if we support digitization of EMG sensors
+ALLOWED_SPACES["emg"] = None  # TODO revise if we support digitization of EMG sensors?
 ALLOWED_SPACES["anat"] = None
 ALLOWED_SPACES["beh"] = None
 

From c84882c0611d9fddb823a4f5b4c00e13a593ae5a Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 22 Jan 2025 14:33:25 -0600
Subject: [PATCH 06/25] fix description (unrelated to EMG)

---
 mne_bids/config.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/mne_bids/config.py b/mne_bids/config.py
index 3b94e16c53..80d71d6caa 100644
--- a/mne_bids/config.py
+++ b/mne_bids/config.py
@@ -469,9 +469,9 @@
     for sym in ("Sym", "Asym"):
         BIDS_COORD_FRAME_DESCRIPTIONS[f"mni152nlin2009{letter}{sym}"] = (
             "Also known as ICBM (non-linear coregistration with 40 iterations,"
+            " released in 2009). It comes in three different flavours "
+            "each in symmetric or asymmetric version."
         )
-        " released in 2009). It comes in either three different flavours "
-        "each in symmetric or asymmetric version."
 
 REFERENCES = {
     "mne-bids": "Appelhoff, S., Sanderson, M., Brooks, T., Vliet, M., "

From f3453063fdcf6c30a9fa6ff58b62360a45126b42 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 22 Jan 2025 14:34:08 -0600
Subject: [PATCH 07/25] uncomment JSON fields

---
 mne_bids/write.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/mne_bids/write.py b/mne_bids/write.py
index cc51ecfd73..da80cb190b 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -1006,10 +1006,10 @@ def _sidecar_json(
     ]
 
     ch_info_json_emg = [
-        # ("EEGReference", "n/a"),
-        # ("EEGGround", "n/a"),
-        # ("EEGPlacementScheme", _infer_eeg_placement_scheme(raw)),
-        # ("Manufacturer", manufacturer)
+        ("EMGReference", "n/a"),
+        ("EMGGround", "n/a"),
+        ("EMGPlacementScheme", "n/a"),
+        ("Manufacturer", manufacturer),
     ]
 
     ch_info_json_ieeg = [

From 347dab740243f42cccf1940ee48f404c366f63d0 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 19 Mar 2025 10:49:10 -0500
Subject: [PATCH 08/25] more WIP changes [ci skip]

---
 mne_bids/config.py |  5 +++++
 mne_bids/utils.py  |  5 +++++
 mne_bids/write.py  | 20 ++++++++++++++++++--
 3 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/mne_bids/config.py b/mne_bids/config.py
index 80d71d6caa..41683c7d7c 100644
--- a/mne_bids/config.py
+++ b/mne_bids/config.py
@@ -19,11 +19,13 @@
 
 MEG_CONVERT_FORMATS = ["FIF", "auto"]
 EEG_CONVERT_FORMATS = ["BrainVision", "auto"]
+EMG_CONVERT_FORMATS = ["EDF", "BDF", "auto"]
 IEEG_CONVERT_FORMATS = ["BrainVision", "auto"]
 NIRS_CONVERT_FORMATS = ["auto"]
 CONVERT_FORMATS = {
     "meg": MEG_CONVERT_FORMATS,
     "eeg": EEG_CONVERT_FORMATS,
+    "emg": EMG_CONVERT_FORMATS,
     "ieeg": IEEG_CONVERT_FORMATS,
     "nirs": NIRS_CONVERT_FORMATS,
 }
@@ -140,6 +142,9 @@
 
 allowed_extensions_emg = [
     ".edf",  # European Data Format
+    ".bdf",  # Biosemi
+    # TODO EMG: .bdf support awaits https://github.com/the-siesta-group/edfio/issues/62
+    # and corresponding downstream changes in MNE-Python and here in MNE-BIDS
 ]
 
 allowed_extensions_ieeg = [
diff --git a/mne_bids/utils.py b/mne_bids/utils.py
index bbd9b150a8..709778a1bb 100644
--- a/mne_bids/utils.py
+++ b/mne_bids/utils.py
@@ -294,6 +294,11 @@ def _get_mrk_meas_date(mrk):
     return meas_datetime
 
 
+def _infer_emg_placement_scheme(raw):
+    # TODO EMG: just a placeholder, may not even need to exist in the end
+    pass
+
+
 def _infer_eeg_placement_scheme(raw):
     """Based on the channel names, try to infer an EEG placement scheme.
 
diff --git a/mne_bids/write.py b/mne_bids/write.py
index da80cb190b..da9c2be96c 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -79,6 +79,7 @@
     _handle_datatype,
     _import_nibabel,
     _infer_eeg_placement_scheme,
+    _infer_emg_placement_scheme,
     _stamp_to_dt,
     _write_json,
     _write_text,
@@ -1008,7 +1009,8 @@ def _sidecar_json(
     ch_info_json_emg = [
         ("EMGReference", "n/a"),
         ("EMGGround", "n/a"),
-        ("EMGPlacementScheme", "n/a"),
+        # TODO EMG: must be one of Measured, ChannelSpecific, Other
+        ("EMGPlacementScheme", _infer_emg_placement_scheme(raw)),
         ("Manufacturer", manufacturer),
     ]
 
@@ -2050,6 +2052,10 @@ def write_raw_bids(
         # if we have an available DigMontage
         if montage is not None or (raw.info["dig"] is not None and raw.info["dig"]):
             _write_dig_bids(bids_path, raw, montage, acpc_aligned, overwrite)
+    elif bids_path.datatype == "emg":
+        # TODO EMG: this is where to handle EMG coordsystem. We're not going to have a
+        #           DigMontage (probably) so need another way to intake the info
+        pass
     else:
         logger.info(
             f"Writing of electrodes.tsv is not supported "
@@ -2202,12 +2208,22 @@ def write_raw_bids(
                     else bids_path.fpath
                 ),
             )
-        elif bids_path.datatype in ["eeg", "ieeg"] and format == "EDF":
+        elif bids_path.datatype in ["eeg", "emg", "ieeg"] and format == "EDF":
             warn("Converting data files to EDF format")
+            bids_path.update(extension=".edf")
             _write_raw_edf(raw, bids_path.fpath, overwrite=overwrite)
+        elif bids_path.datatype in ["emg"] and format == "BDF":
+            # TODO EMG
+            raise NotImplementedError("Conversion to BDF not yet supported.")
         elif bids_path.datatype in ["eeg", "ieeg"] and format == "EEGLAB":
             warn("Converting data files to EEGLAB format")
             _write_raw_eeglab(raw, bids_path.fpath, overwrite=overwrite)
+        elif bids_path.datatype in ["emg"]:
+            # TODO EMG: when writing to BDF is possible, that will be the default here
+            # instead. cf: https://github.com/the-siesta-group/edfio/issues/62
+            bids_path.update(extension=".edf")
+            warn("Converting data files to EDF format")
+            _write_raw_edf(raw, bids_path.fpath, overwrite=overwrite)
         else:
             warn("Converting data files to BrainVision format")
             bids_path.update(suffix=bids_path.datatype, extension=".vhdr")

From acdcc185c13b3b4dec60c88e81619c5c54a0848d Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 26 Mar 2025 16:19:07 -0500
Subject: [PATCH 09/25] make EMG a valid datatype

---
 mne_bids/utils.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/mne_bids/utils.py b/mne_bids/utils.py
index 709778a1bb..2cc0b0993e 100644
--- a/mne_bids/utils.py
+++ b/mne_bids/utils.py
@@ -495,7 +495,7 @@ def _check_datatype(raw, datatype):
     -------
     None
     """
-    supported_types = ("meg", "eeg", "ieeg", "nirs")
+    supported_types = ("meg", "eeg", "emg", "ieeg", "nirs")
     if datatype not in supported_types:
         raise ValueError(
             f"The specified datatype {datatype} is currently not supported. "
@@ -506,6 +506,8 @@ def _check_datatype(raw, datatype):
     datatype_matches = False
     if datatype == "eeg" and datatype in raw:
         datatype_matches = True
+    elif datatype == "emg" and datatype in raw:
+        datatype_matches = True
     elif datatype == "meg" and datatype in raw:
         datatype_matches = True
     elif datatype == "nirs" and "fnirs_cw_amplitude" in raw:

From 97397a744fc5a0a26a0f297a7b92ed0108949efd Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 26 Mar 2025 16:32:21 -0500
Subject: [PATCH 10/25] update EMG TODO comments

---
 mne_bids/utils.py |  5 -----
 mne_bids/write.py | 28 +++++++++++++++++-----------
 2 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/mne_bids/utils.py b/mne_bids/utils.py
index 2cc0b0993e..14d69a705e 100644
--- a/mne_bids/utils.py
+++ b/mne_bids/utils.py
@@ -294,11 +294,6 @@ def _get_mrk_meas_date(mrk):
     return meas_datetime
 
 
-def _infer_emg_placement_scheme(raw):
-    # TODO EMG: just a placeholder, may not even need to exist in the end
-    pass
-
-
 def _infer_eeg_placement_scheme(raw):
     """Based on the channel names, try to infer an EEG placement scheme.
 
diff --git a/mne_bids/write.py b/mne_bids/write.py
index da9c2be96c..82b3fdc37a 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -79,7 +79,6 @@
     _handle_datatype,
     _import_nibabel,
     _infer_eeg_placement_scheme,
-    _infer_emg_placement_scheme,
     _stamp_to_dt,
     _write_json,
     _write_text,
@@ -1009,8 +1008,9 @@ def _sidecar_json(
     ch_info_json_emg = [
         ("EMGReference", "n/a"),
         ("EMGGround", "n/a"),
-        # TODO EMG: must be one of Measured, ChannelSpecific, Other
-        ("EMGPlacementScheme", _infer_emg_placement_scheme(raw)),
+        # TODO EMG: must be one of Measured, ChannelSpecific, or Other, so writing `n/a`
+        # will lead to a dataset that doesn't validate.
+        ("EMGPlacementScheme", "n/a"),
         ("Manufacturer", manufacturer),
     ]
 
@@ -2047,15 +2047,21 @@ def write_raw_bids(
             datatype=bids_path.datatype,
             overwrite=overwrite,
         )
-    elif bids_path.datatype in ["eeg", "ieeg", "nirs"]:
+    elif bids_path.datatype in ["eeg", "emg", "ieeg", "nirs"]:
         # We only write electrodes.tsv and accompanying coordsystem.json
         # if we have an available DigMontage
-        if montage is not None or (raw.info["dig"] is not None and raw.info["dig"]):
+        if montage is not None or raw.info["dig"]:
             _write_dig_bids(bids_path, raw, montage, acpc_aligned, overwrite)
-    elif bids_path.datatype == "emg":
-        # TODO EMG: this is where to handle EMG coordsystem. We're not going to have a
-        #           DigMontage (probably) so need another way to intake the info
-        pass
+        elif bids_path.datatype == "emg":
+            # TODO EMG: Handle EMG coordsystem if it's not in `raw.info["dig"]`.
+            # In theory we could make a helper func for creating a `DigMontage` from
+            # EMG electrode location info, and users could pass that into
+            # `write_raw_bids`...
+            warn(
+                "No electrode location info found in raw file, so not writing "
+                "coordinate system info for EMG data. Please add `coordsystem.json` "
+                "file manually."
+            )
     else:
         logger.info(
             f"Writing of electrodes.tsv is not supported "
@@ -2213,8 +2219,8 @@ def write_raw_bids(
             bids_path.update(extension=".edf")
             _write_raw_edf(raw, bids_path.fpath, overwrite=overwrite)
         elif bids_path.datatype in ["emg"] and format == "BDF":
-            # TODO EMG
-            raise NotImplementedError("Conversion to BDF not yet supported.")
+            # TODO EMG cf: https://github.com/the-siesta-group/edfio/issues/62
+            raise NotImplementedError("Conversion to BDF is not yet supported.")
         elif bids_path.datatype in ["eeg", "ieeg"] and format == "EEGLAB":
             warn("Converting data files to EEGLAB format")
             _write_raw_eeglab(raw, bids_path.fpath, overwrite=overwrite)

From 28a4c78983a3d406fd3f8b651f38929c3710b8e5 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Fri, 24 Oct 2025 17:28:43 -0500
Subject: [PATCH 11/25] add BDF export; handle coordsys spaces

---
 mne_bids/config.py | 25 ++++++++++++++++-----
 mne_bids/write.py  | 56 +++++++++++++++++++++++++++++++++++++---------
 2 files changed, 66 insertions(+), 15 deletions(-)

diff --git a/mne_bids/config.py b/mne_bids/config.py
index 54bf4a632d..14ea42ddfa 100644
--- a/mne_bids/config.py
+++ b/mne_bids/config.py
@@ -13,7 +13,7 @@
 
 DOI = """https://doi.org/10.21105/joss.01896"""
 
-EPHY_ALLOWED_DATATYPES = ["meg", "eeg", "ieeg", "nirs", "emg"]
+EPHY_ALLOWED_DATATYPES = ["eeg", "emg", "ieeg", "meg", "nirs"]
 
 ALLOWED_DATATYPES = EPHY_ALLOWED_DATATYPES + ["anat", "beh", "motion"]
 
@@ -88,7 +88,12 @@
     ".EEG": "Nihon Kohden",
 }
 
-emg_manufacturers = {}  # TODO
+emg_manufacturers = {
+    ".edf": "n/a",
+    ".EDF": "n/a",
+    ".bdf": "Biosemi",
+    ".BDF": "Biosemi",
+}
 
 nirs_manufacturers = {".snirf": "SNIRF"}
 
@@ -145,8 +150,6 @@
 allowed_extensions_emg = [
     ".edf",  # European Data Format
     ".bdf",  # Biosemi
-    # TODO EMG: .bdf support awaits https://github.com/the-siesta-group/edfio/issues/62
-    # and corresponding downstream changes in MNE-Python and here in MNE-BIDS
 ]
 
 allowed_extensions_ieeg = [
@@ -340,6 +343,18 @@
     + coordsys_wildcard
 )
 
+
+# EMG allows arbitrary (user-defined) coord frames
+class EmgCoordFrames(list):
+    """Container for arbitrary (user-defined) coordinate frames (spaces)."""
+
+    def __contains__(self, item):
+        """Pretends to contain any non-empty string."""
+        return isinstance(item, str) and len(item)
+
+
+BIDS_EMG_COORDINATE_FRAMES = EmgCoordFrames()
+
 ALLOWED_SPACES = dict()
 ALLOWED_SPACES["meg"] = ALLOWED_SPACES["eeg"] = (
     BIDS_SHARED_COORDINATE_FRAMES
@@ -347,7 +362,7 @@
     + BIDS_EEG_COORDINATE_FRAMES
 )
 ALLOWED_SPACES["ieeg"] = BIDS_SHARED_COORDINATE_FRAMES + BIDS_IEEG_COORDINATE_FRAMES
-ALLOWED_SPACES["emg"] = None  # TODO revise if we support digitization of EMG sensors?
+ALLOWED_SPACES["emg"] = BIDS_EMG_COORDINATE_FRAMES
 ALLOWED_SPACES["anat"] = None
 ALLOWED_SPACES["beh"] = None
 ALLOWED_SPACES["motion"] = None
diff --git a/mne_bids/write.py b/mne_bids/write.py
index d178189b24..25351ec73b 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -879,7 +879,15 @@ def _mri_scanner_ras_to_mri_voxels(ras_landmarks, img_mgh):
 
 
 def _sidecar_json(
-    raw, task, manufacturer, fname, datatype, emptyroom_fname=None, overwrite=False
+    raw,
+    task,
+    manufacturer,
+    fname,
+    datatype,
+    *,
+    emg_placement=None,
+    emptyroom_fname=None,
+    overwrite=False,
 ):
     """Create a sidecar json file depending on the suffix and save it.
 
@@ -899,6 +907,9 @@ def _sidecar_json(
         Filename to save the sidecar json to.
     datatype : str
         Type of the data as in ALLOWED_ELECTROPHYSIO_DATATYPE.
+    emg_placement : "Measured" | "ChannelSpecific" | "Other" | None
+        How the EMG sensor locations were determined. Must be one of the literal strings
+        if ``datatype="emg"`` and should be ``None`` for all other datatypes.
     emptyroom_fname : str | mne_bids.BIDSPath
         For MEG recordings, the path to an empty-room data file to be
         associated with ``raw``. Only supported for MEG.
@@ -1050,9 +1061,9 @@ def _sidecar_json(
     ch_info_json_emg = [
         ("EMGReference", "n/a"),
         ("EMGGround", "n/a"),
-        # TODO EMG: must be one of Measured, ChannelSpecific, or Other, so writing `n/a`
-        # will lead to a dataset that doesn't validate.
-        ("EMGPlacementScheme", "n/a"),
+        # n/a will fail to validate, but if emg_placement is None that's our bug:
+        # the user-called function write_raw_bids should guarantee a valid string here
+        ("EMGPlacementScheme", emg_placement or "n/a"),
         ("Manufacturer", manufacturer),
     ]
 
@@ -1269,6 +1280,22 @@ def _write_raw_brainvision(raw, bids_fname, events, overwrite):
     )
 
 
+def _write_raw_bdf(raw, bids_fname, overwrite):
+    """Store data as BDF.
+
+    Parameters
+    ----------
+    raw : mne.io.Raw
+        Raw data to save.
+    bids_fname : str
+        The output filename.
+    overwrite : bool
+        Whether to overwrite an existing file or not.
+    """
+    assert str(bids_fname).endswith(".bdf")
+    raw.export(bids_fname, overwrite=overwrite)
+
+
 def _write_raw_edf(raw, bids_fname, overwrite):
     """Store data as EDF.
 
@@ -1511,6 +1538,7 @@ def write_raw_bids(
     montage=None,
     acpc_aligned=False,
     electrodes_tsv_task=False,
+    emg_placement=None,
     overwrite=False,
     verbose=None,
 ):
@@ -1690,6 +1718,9 @@ def write_raw_bids(
     electrodes_tsv_task : bool
         Add the ``task-`` entity to the ``electrodes.tsv`` filename.
         Defaults to ``False``.
+    emg_placement : "Measured" | "ChannelSpecific" | "Other" | None
+        How the EMG sensor locations were determined. Must be one of the literal strings
+        if datatype is "emg" and should be ``None`` for all other datatypes.
     overwrite : bool
         Whether to overwrite existing files or data in files.
         Defaults to ``False``.
@@ -1927,6 +1958,12 @@ def write_raw_bids(
         datatype=datatype, suffix=datatype, extension=ext
     )
 
+    if datatype == "emg" and emg_placement is None:
+        raise ValueError(
+            '`emg_placement` must be one of "Measured", "ChannelSpecific", or "Other" '
+            f"(got {emg_placement})"
+        )
+
     # Check whether provided info and raw indicates valid MEG emptyroom data
     data_is_emptyroom = False
     if (
@@ -2188,6 +2225,7 @@ def write_raw_bids(
         fname=sidecar_path.fpath,
         datatype=bids_path.datatype,
         emptyroom_fname=associated_er_path,
+        emg_placement=emg_placement,
         overwrite=overwrite,
     )
     _channels_tsv(raw, channels_path.fpath, overwrite)
@@ -2293,16 +2331,14 @@ def write_raw_bids(
             bids_path.update(extension=".edf")
             _write_raw_edf(raw, bids_path.fpath, overwrite=overwrite)
         elif bids_path.datatype in ["emg"] and format == "BDF":
-            # TODO EMG cf: https://github.com/the-siesta-group/edfio/issues/62
-            raise NotImplementedError("Conversion to BDF is not yet supported.")
+            bids_path.update(extension=".bdf")
+            _write_raw_bdf(raw, bids_path.fpath, overwrite=overwrite)
         elif bids_path.datatype in ["eeg", "ieeg"] and format == "EEGLAB":
             warn("Converting data files to EEGLAB format")
             _write_raw_eeglab(raw, bids_path.fpath, overwrite=overwrite)
         elif bids_path.datatype in ["emg"]:
-            # TODO EMG: when writing to BDF is possible, that will be the default here
-            # instead. cf: https://github.com/the-siesta-group/edfio/issues/62
-            bids_path.update(extension=".edf")
-            warn("Converting data files to EDF format")
+            bids_path.update(extension=".bdf")
+            warn("Converting data files to BDF format")
             _write_raw_edf(raw, bids_path.fpath, overwrite=overwrite)
         else:
             warn("Converting data files to BrainVision format")

From 39c745b4dc3aec0add6e8edb1440228aa85d6c8f Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Mon, 27 Oct 2025 09:01:43 -0500
Subject: [PATCH 12/25] fix test err match

---
 mne_bids/tests/test_utils.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mne_bids/tests/test_utils.py b/mne_bids/tests/test_utils.py
index 47b4c4393a..450cd72a21 100644
--- a/mne_bids/tests/test_utils.py
+++ b/mne_bids/tests/test_utils.py
@@ -108,7 +108,7 @@ def test_handle_datatype():
             _handle_datatype(raw, datatype)
     # if proper channel type (iEEG, EEG or MEG) is not found, raise ValueError
     ch_type = ["misc"]
-    with pytest.raises(ValueError, match="No MEG, EEG or iEEG channels found"):
+    with pytest.raises(ValueError, match="No MEG, EEG, iEEG, or EMG channels found"):
         info = mne.create_info(n_channels, sampling_rate, ch_types=ch_type * 2)
         raw = mne.io.RawArray(data, info)
         _handle_datatype(raw, datatype)

From a27a7a23abf737e8feb58c2cad092463ceb6b1cd Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Mon, 27 Oct 2025 09:13:28 -0500
Subject: [PATCH 13/25] add EMG to valid read lists (and sort those lists)

---
 mne_bids/path.py | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/mne_bids/path.py b/mne_bids/path.py
index 996e4642c5..b7de8768bb 100644
--- a/mne_bids/path.py
+++ b/mne_bids/path.py
@@ -1939,7 +1939,18 @@ def get_datatypes(root, verbose=None):
     # Take all possible data types from "entity" table
     # (Appendix in BIDS spec)
     # https://bids-specification.readthedocs.io/en/latest/appendices/entity-table.html
-    datatype_list = ("anat", "func", "dwi", "fmap", "beh", "meg", "eeg", "ieeg", "nirs")
+    datatype_list = (
+        "anat",
+        "beh",
+        "dwi",
+        "eeg",
+        "emg",
+        "fmap",
+        "func",
+        "ieeg",
+        "meg",
+        "nirs",
+    )
     datatypes = list()
     for root, dirs, files in os.walk(root):
         for _dir in dirs:
@@ -2301,7 +2312,7 @@ def _infer_datatype(*, root, sub, ses):
     modalities = _get_datatypes_for_sub(root=root, sub=sub, ses=ses)
 
     # We only want to handle electrophysiological data here.
-    allowed_recording_modalities = ["meg", "eeg", "ieeg"]
+    allowed_recording_modalities = ["eeg", "emg", "ieeg", "meg"]
     modalities = list(set(modalities) & set(allowed_recording_modalities))
     if not modalities:
         raise ValueError("No electrophysiological data found.")

From 397759061115b90dcfe5ba1f316ccfefe58c6a9f Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Mon, 27 Oct 2025 09:17:56 -0500
Subject: [PATCH 14/25] sort another one

---
 mne_bids/utils.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mne_bids/utils.py b/mne_bids/utils.py
index 7651115d1b..66b7d611a0 100644
--- a/mne_bids/utils.py
+++ b/mne_bids/utils.py
@@ -491,7 +491,7 @@ def _check_datatype(raw, datatype):
     -------
     None
     """
-    supported_types = ("meg", "eeg", "emg", "ieeg", "nirs")
+    supported_types = ("eeg", "emg", "ieeg", "meg", "nirs")
     if datatype not in supported_types:
         raise ValueError(
             f"The specified datatype {datatype} is currently not supported. "

From f4e0a03edc30595c8722b1d25d2922cc45c482f2 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Mon, 27 Oct 2025 11:54:03 -0500
Subject: [PATCH 15/25] actually enable BDF writing

---
 mne_bids/write.py | 49 +++++++++++++++++++++--------------------------
 1 file changed, 22 insertions(+), 27 deletions(-)

diff --git a/mne_bids/write.py b/mne_bids/write.py
index 25351ec73b..b0165d985b 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -1280,23 +1280,7 @@ def _write_raw_brainvision(raw, bids_fname, events, overwrite):
     )
 
 
-def _write_raw_bdf(raw, bids_fname, overwrite):
-    """Store data as BDF.
-
-    Parameters
-    ----------
-    raw : mne.io.Raw
-        Raw data to save.
-    bids_fname : str
-        The output filename.
-    overwrite : bool
-        Whether to overwrite an existing file or not.
-    """
-    assert str(bids_fname).endswith(".bdf")
-    raw.export(bids_fname, overwrite=overwrite)
-
-
-def _write_raw_edf(raw, bids_fname, overwrite):
+def _write_raw_edf_bdf(raw, bids_fname, overwrite):
     """Store data as EDF.
 
     Parameters
@@ -1308,7 +1292,7 @@ def _write_raw_edf(raw, bids_fname, overwrite):
     overwrite : bool
         Whether to overwrite an existing file or not.
     """
-    assert str(bids_fname).endswith(".edf")
+    assert bids_fname.suffix in (".edf", ".bdf")
     raw.export(bids_fname, overwrite=overwrite)
 
 
@@ -1657,14 +1641,14 @@ def write_raw_bids(
             ``source`` column of ``scans.tsv``. By default, this information
             is not stored.
 
-    format : 'auto' | 'BrainVision' | 'EDF' | 'FIF' | 'EEGLAB'
+    format : 'auto' | 'BrainVision' | 'BDF' | 'EDF' | 'FIF' | 'EEGLAB'
         Controls the file format of the data after BIDS conversion. If
         ``'auto'``, MNE-BIDS will attempt to convert the input data to BIDS
         without a change of the original file format. A conversion to a
         different file format will then only take place if the original file
         format lacks some necessary features.
         Conversion may be forced to BrainVision, EDF, or EEGLAB for (i)EEG,
-        and to FIF for MEG data.
+        to BDF or EDF for EMG, and to FIF for MEG data.
     symlink : bool
         Instead of copying the source files, only create symbolic links to
         preserve storage space. This is only allowed when not anonymizing the
@@ -1905,6 +1889,8 @@ def write_raw_bids(
     else:
         if format == "BrainVision":
             ext = ".vhdr"
+        elif format == "BDF":
+            ext = ".bdf"
         elif format == "EDF":
             ext = ".edf"
         elif format == "EEGLAB":
@@ -1914,7 +1900,7 @@ def write_raw_bids(
         else:
             msg = (
                 'For preloaded data, you must set the "format" parameter '
-                "to one of: BrainVision, EDF, EEGLAB, or FIF"
+                "to one of: BrainVision, BDF, EDF, EEGLAB, or FIF"
             )
             if format != "auto":  # the default was changed
                 msg += f', but got: "{format}"'
@@ -2108,6 +2094,12 @@ def write_raw_bids(
                 warn("Converting data files to BrainVision format for anonymization")
                 convert = True
                 bids_path.update(extension=".vhdr")
+        elif bids_path.datatype == "emg":
+            if ext not in [".edf", ".bdf", ".EDF", ".BDF"]:
+                warn("Converting data files to BDF format for anonymization")
+                convert = True
+                bids_path.update(extension=".bdf")
+
     # Read in Raw object and extract metadata from Raw object if needed
     orient = ORIENTATION.get(ext, "n/a")
     unit = EXT_TO_UNIT_MAP.get(ext, "n/a")
@@ -2263,9 +2255,12 @@ def write_raw_bids(
         if format == "BrainVision" and bids_path.datatype in ["ieeg", "eeg"]:
             convert = True
             bids_path.update(extension=".vhdr")
-        elif format == "EDF" and bids_path.datatype in ["ieeg", "eeg"]:
+        elif format == "EDF" and bids_path.datatype in ["ieeg", "eeg", "emg"]:
             convert = True
             bids_path.update(extension=".edf")
+        elif format == "BDF" and bids_path.datatype in ["emg"]:
+            convert = True
+            bids_path.update(extension=".bdf")
         elif format == "EEGLAB" and bids_path.datatype in ["ieeg", "eeg"]:
             convert = True
             bids_path.update(extension=".set")
@@ -2326,20 +2321,20 @@ def write_raw_bids(
                     else bids_path.fpath
                 ),
             )
+        elif bids_path.datatype in ["emg"] and format == "BDF":
+            bids_path.update(extension=".bdf")
+            _write_raw_edf_bdf(raw, bids_path.fpath, overwrite=overwrite)
         elif bids_path.datatype in ["eeg", "emg", "ieeg"] and format == "EDF":
             warn("Converting data files to EDF format")
             bids_path.update(extension=".edf")
-            _write_raw_edf(raw, bids_path.fpath, overwrite=overwrite)
-        elif bids_path.datatype in ["emg"] and format == "BDF":
-            bids_path.update(extension=".bdf")
-            _write_raw_bdf(raw, bids_path.fpath, overwrite=overwrite)
+            _write_raw_edf_bdf(raw, bids_path.fpath, overwrite=overwrite)
         elif bids_path.datatype in ["eeg", "ieeg"] and format == "EEGLAB":
             warn("Converting data files to EEGLAB format")
             _write_raw_eeglab(raw, bids_path.fpath, overwrite=overwrite)
         elif bids_path.datatype in ["emg"]:
             bids_path.update(extension=".bdf")
             warn("Converting data files to BDF format")
-            _write_raw_edf(raw, bids_path.fpath, overwrite=overwrite)
+            _write_raw_edf_bdf(raw, bids_path.fpath, overwrite=overwrite)
         else:
             warn("Converting data files to BrainVision format")
             bids_path.update(suffix=bids_path.datatype, extension=".vhdr")

From 8cf38c343a3261be183c36da5345e41942bb7bb3 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Mon, 27 Oct 2025 16:46:57 -0500
Subject: [PATCH 16/25] coverage

---
 mne_bids/tests/test_write.py | 38 ++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)

diff --git a/mne_bids/tests/test_write.py b/mne_bids/tests/test_write.py
index ec1c1ca314..ec62d46388 100644
--- a/mne_bids/tests/test_write.py
+++ b/mne_bids/tests/test_write.py
@@ -96,6 +96,8 @@
     no_hand=r"ignore:Unable to map.*\n.*subject handedness.*:RuntimeWarning:mne",
     no_montage=r"ignore:Not setting position of.*channel found in "
     r"montage.*:RuntimeWarning:mne",
+    emg_coords_missing=r"ignore:No electrode location info found.*:RuntimeWarning",
+    converting_to_edf=r"ignore:Converting data files to EDF format:RuntimeWarning",
 )
 
 
@@ -174,6 +176,10 @@ def fn(fname, *args, **kwargs):
     ("CNT", "EDF", "scan41_short.cnt", _read_raw_cnt),
     ("curry", "EDF", "test_bdf_stim_channel Curry 8.cdt", _read_raw_curry),
 ]
+test_convertemg_data = [
+    ("BDF", "EDF", "test_generator_2.bdf", _read_raw_bdf),
+    ("EDF", "BDF", "test_generator_2.edf", _read_raw_edf),
+]
 
 data_path = testing.data_path(download=False)
 
@@ -3319,6 +3325,38 @@ def test_sidecar_encoding(_bids_validate, tmp_path):
     assert_array_equal(raw.annotations.description, raw_read.annotations.description)
 
 
+@pytest.mark.parametrize("dir_name, fmt, fname, reader", test_convertemg_data)
+@pytest.mark.filterwarnings(
+    warning_str["emg_coords_missing"],
+    warning_str["converting_to_edf"],
+)
+@testing.requires_testing_data
+def test_convert_emg_formats(tmp_path, dir_name, fmt, fname, reader):
+    """Test EDF ←→ BDF conversion of EMG datasets."""
+    bids_root = tmp_path / fmt
+    raw_fname = data_path / dir_name / fname
+    bids_path = _bids_path.copy().update(root=bids_root, datatype="emg")
+    raw = reader(raw_fname)
+    raw.set_channel_types({ch: "emg" for ch in raw.ch_names})  # HACK eeg → emg
+    raw = raw.pick(["emg"])  # drop misc
+    # make sure it's possible to define arbitrarily-named coordsys spaces for EMG
+    bids_path.update(space="foo", check=True)
+    bids_output_path = write_raw_bids(
+        raw=raw,
+        format=fmt,
+        bids_path=bids_path,
+        overwrite=True,
+        verbose=False,
+        emg_placement="Other",
+    )
+    # make sure the file extension is correct (different from what we started with)
+    outdir = tmp_path / fmt / "sub-01" / "ses-01" / "emg"
+    dont_want = list((outdir).glob(f"*{raw_fname.suffix}"))
+    want = list((outdir).glob(f"*.{fmt.lower()}"))
+    assert len(dont_want) == 0
+    assert want == [bids_output_path.fpath]
+
+
 @pytest.mark.parametrize("dir_name, fmt, fname, reader", test_converteeg_data)
 @pytest.mark.filterwarnings(
     warning_str["channel_unit_changed"],

From 7432abae303b6cc04402d91151354ebe8fc35b68 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Tue, 4 Nov 2025 10:29:43 -0600
Subject: [PATCH 17/25] fix test (MNE minversion)

---
 mne_bids/tests/test_write.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mne_bids/tests/test_write.py b/mne_bids/tests/test_write.py
index ec62d46388..3840a01fd4 100644
--- a/mne_bids/tests/test_write.py
+++ b/mne_bids/tests/test_write.py
@@ -3333,6 +3333,7 @@ def test_sidecar_encoding(_bids_validate, tmp_path):
 @testing.requires_testing_data
 def test_convert_emg_formats(tmp_path, dir_name, fmt, fname, reader):
     """Test EDF ←→ BDF conversion of EMG datasets."""
+    pytest.importorskip("mne", minversion="1.10.2", reason="BDF export")
     bids_root = tmp_path / fmt
     raw_fname = data_path / dir_name / fname
     bids_path = _bids_path.copy().update(root=bids_root, datatype="emg")

From 571f7c290dbbac86d51c610083cbf1af1e418374 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Tue, 4 Nov 2025 10:29:54 -0600
Subject: [PATCH 18/25] add missing metadata key

---
 mne_bids/write.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/mne_bids/write.py b/mne_bids/write.py
index b0165d985b..189f794c2a 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -1066,6 +1066,10 @@ def _sidecar_json(
         ("EMGPlacementScheme", emg_placement or "n/a"),
         ("Manufacturer", manufacturer),
     ]
+    if emg_placement == "Other":
+        ch_info_json_emg.append(
+            ("EMGPlacementSchemeDescription", "TODO FIXME please complete this field")
+        )
 
     ch_info_json_ieeg = [
         ("iEEGReference", "n/a"),

From 44ce4cceac6e83df9128183cc3253250b7e74fb3 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 5 Nov 2025 11:28:57 -0600
Subject: [PATCH 19/25] more coverage

---
 mne_bids/tests/test_write.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/mne_bids/tests/test_write.py b/mne_bids/tests/test_write.py
index dc8b9243ab..c7e88ac70e 100644
--- a/mne_bids/tests/test_write.py
+++ b/mne_bids/tests/test_write.py
@@ -87,7 +87,7 @@
     edf_warning=r"ignore:^EDF\/EDF\+\/BDF files contain two fields .*"
     r":RuntimeWarning:mne",
     maxshield="ignore:.*Internal Active Shielding:RuntimeWarning:mne",
-    edfblocks="ignore:.*EDF format requires equal-length data "
+    edfblocks="ignore:.*[BE]DF format requires equal-length data "
     "blocks:RuntimeWarning:mne",
     brainvision_unit="ignore:Encountered unsupported non-voltage units*.:UserWarning",
     cnt_warning1="ignore:.*Could not parse meas date from the header. Setting to None.",
@@ -220,6 +220,7 @@ def fn(fname, *args, **kwargs):
 test_convertemg_data = [
     ("BDF", "EDF", "test_generator_2.bdf", _read_raw_bdf),
     ("EDF", "BDF", "test_generator_2.edf", _read_raw_edf),
+    ("Brainvision", "BDF", "test_NO.vhdr", _read_raw_brainvision),
 ]
 
 data_path = testing.data_path(download=False)
@@ -3369,6 +3370,7 @@ def test_sidecar_encoding(_bids_validate, tmp_path):
 
 @pytest.mark.parametrize("dir_name, fmt, fname, reader", test_convertemg_data)
 @pytest.mark.filterwarnings(
+    warning_str["edfblocks"],
     warning_str["emg_coords_missing"],
     warning_str["converting_to_edf"],
 )
@@ -3382,6 +3384,9 @@ def test_convert_emg_formats(tmp_path, dir_name, fmt, fname, reader):
     raw = reader(raw_fname)
     raw.set_channel_types({ch: "emg" for ch in raw.ch_names})  # HACK eeg → emg
     raw = raw.pick(["emg"])  # drop misc
+    # test anonymization in one case too, for coverage
+    if dir_name == "Brainvision":
+        raw.anonymize()
     # make sure it's possible to define arbitrarily-named coordsys spaces for EMG
     bids_path.update(space="foo", check=True)
     bids_output_path = write_raw_bids(

From 08e6939aa2e5f9b2369083d4e8c399065c63604b Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Wed, 5 Nov 2025 12:11:32 -0600
Subject: [PATCH 20/25] more more coverage

---
 mne_bids/tests/test_write.py | 16 ++++++++++++++++
 mne_bids/write.py            |  6 +++++-
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/mne_bids/tests/test_write.py b/mne_bids/tests/test_write.py
index c7e88ac70e..5fee71a3cb 100644
--- a/mne_bids/tests/test_write.py
+++ b/mne_bids/tests/test_write.py
@@ -3368,6 +3368,22 @@ def test_sidecar_encoding(_bids_validate, tmp_path):
     assert_array_equal(raw.annotations.description, raw_read.annotations.description)
 
 
+@testing.requires_testing_data
+def test_emg_errors_and_warnings(tmp_path):
+    """Test EMG-specific error/warning raising."""
+    bids_root = tmp_path / "EDF"
+    raw_fname = data_path / "EDF" / "test_generator_2.edf"
+    bids_path = _bids_path.copy().update(root=bids_root, datatype="emg")
+    raw = _read_raw_edf(raw_fname)
+    raw.set_channel_types({ch: "emg" for ch in raw.ch_names})  # HACK eeg → emg
+    raw = raw.pick(["emg"])  # drop misc
+    good_kwargs = dict(raw=raw, bids_path=bids_path, verbose=False)
+    with pytest.raises(ValueError, match="`emg_placement` must be one of"):
+        write_raw_bids(**good_kwargs, emg_placement="Foo")
+    with pytest.warns(RuntimeWarning, match="add `coordsystem.json` file manually"):
+        write_raw_bids(**good_kwargs, emg_placement="Other")
+
+
 @pytest.mark.parametrize("dir_name, fmt, fname, reader", test_convertemg_data)
 @pytest.mark.filterwarnings(
     warning_str["edfblocks"],
diff --git a/mne_bids/write.py b/mne_bids/write.py
index a5a35cec4c..3af0c3bf7a 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -2008,7 +2008,11 @@ def write_raw_bids(
         datatype=datatype, suffix=datatype, extension=ext
     )
 
-    if datatype == "emg" and emg_placement is None:
+    if datatype == "emg" and emg_placement not in (
+        "Measured",
+        "ChannelSpecific",
+        "Other",
+    ):
         raise ValueError(
             '`emg_placement` must be one of "Measured", "ChannelSpecific", or "Other" '
             f"(got {emg_placement})"

From b89c159507d63c4191cb625da170a827bb1ddcc1 Mon Sep 17 00:00:00 2001
From: Alexandre Gramfort <agramfort@fb.com>
Date: Sat, 8 Nov 2025 11:16:54 +0100
Subject: [PATCH 21/25] do not require coordsystem.json for EMG

---
 mne_bids/read.py | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/mne_bids/read.py b/mne_bids/read.py
index 1c690d8723..90a8da7c3f 100644
--- a/mne_bids/read.py
+++ b/mne_bids/read.py
@@ -1143,14 +1143,14 @@ def read_raw_bids(
         bids_path, suffix="coordsystem", extension=".json", on_error=on_error
     )
     if electrodes_fname is not None:
-        if coordsystem_fname is None:
-            raise RuntimeError(
-                f"BIDS mandates that the coordsystem.json "
-                f"should exist if electrodes.tsv does. "
-                f"Please create coordsystem.json for"
-                f"{bids_path.basename}"
-            )
         if datatype in ["meg", "eeg", "ieeg"]:
+            if coordsystem_fname is None:
+                raise RuntimeError(
+                    f"BIDS mandates that the coordsystem.json "
+                    f"should exist if electrodes.tsv does. "
+                    f"Please create coordsystem.json for "
+                    f"{bids_path.basename}"
+                )
             _read_dig_bids(
                 electrodes_fname, coordsystem_fname, raw=raw, datatype=datatype
             )

From 31ee317da2180ec57c5accf4d1d40ac12e0cddc3 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Thu, 6 Nov 2025 08:37:14 -0600
Subject: [PATCH 22/25] coverage + test refactor

---
 mne_bids/tests/test_utils.py |  6 ++-
 mne_bids/tests/test_write.py | 95 +++++++++++++++++++++++++-----------
 mne_bids/utils.py            |  8 ++-
 mne_bids/write.py            | 10 +++-
 4 files changed, 83 insertions(+), 36 deletions(-)

diff --git a/mne_bids/tests/test_utils.py b/mne_bids/tests/test_utils.py
index 450cd72a21..0038b7e92f 100644
--- a/mne_bids/tests/test_utils.py
+++ b/mne_bids/tests/test_utils.py
@@ -84,6 +84,10 @@ def test_handle_datatype():
         assert _handle_datatype(raw, datatype) == datatype
     # datatype is not given, will be inferred if possible
     datatype = None
+    # check basic inference (only one ch_type)
+    info = mne.create_info(n_channels, sampling_rate, ch_types="emg")
+    raw = mne.io.RawArray(random((2, sampling_rate)), info)
+    assert _handle_datatype(raw, datatype) == "emg"
     # check if datatype is correctly inferred (combined EEG and iEEG/MEG data)
     channel_types = [["grad", "eeg"], ["eeg", "mag"], ["eeg", "seeg"], ["ecog", "eeg"]]
     expected_modalities = ["meg", "meg", "ieeg", "ieeg"]
@@ -108,7 +112,7 @@ def test_handle_datatype():
             _handle_datatype(raw, datatype)
     # if proper channel type (iEEG, EEG or MEG) is not found, raise ValueError
     ch_type = ["misc"]
-    with pytest.raises(ValueError, match="No MEG, EEG, iEEG, or EMG channels found"):
+    with pytest.raises(ValueError, match="No MEG, EEG, iEEG, EMG, or fNIRS channels"):
         info = mne.create_info(n_channels, sampling_rate, ch_types=ch_type * 2)
         raw = mne.io.RawArray(data, info)
         _handle_datatype(raw, datatype)
diff --git a/mne_bids/tests/test_write.py b/mne_bids/tests/test_write.py
index 5fee71a3cb..3737829eea 100644
--- a/mne_bids/tests/test_write.py
+++ b/mne_bids/tests/test_write.py
@@ -98,11 +98,12 @@
     no_montage=r"ignore:Not setting position of.*channel found in "
     r"montage.*:RuntimeWarning:mne",
     emg_coords_missing=r"ignore:No electrode location info found.*:RuntimeWarning",
-    converting_to_edf=r"ignore:Converting data files to EDF format:RuntimeWarning",
+    converting_to_edf=r"ignore:Converting data files to [BE]DF format:RuntimeWarning",
     channel_mismatch=(
         "ignore:Channel mismatch between .*channels\\.tsv and the raw data file "
         "detected\\.:RuntimeWarning:mne"
     ),
+    edf_date="ignore:.*limits dates to after 1985-01-01:RuntimeWarning",
 )
 
 
@@ -3173,6 +3174,7 @@ def test_coordsystem_json_compliance(
             "sub-pt1_ses-02_task-monitor_acq-ecog_run-01_clip2.lay",
             _read_raw_persyst,
         ),
+        ("01", "Brainvision", "Analyzer_nV_Export.vhdr", _read_raw_brainvision),
         ("03", "NihonKohden", "MB0400FU.EEG", _read_raw_nihon),
         ("emptyroom", "MEG/sample", "sample_audvis_trunc_raw.fif", _read_raw_fif),
     ],
@@ -3182,10 +3184,14 @@ def test_coordsystem_json_compliance(
     warning_str["channel_unit_changed"],
     warning_str["edf_warning"],
     warning_str["brainvision_unit"],
+    warning_str["converting_to_edf"],
+    warning_str["edfblocks"],
+    warning_str["emg_coords_missing"],
+    warning_str["edf_date"],
 )
 @testing.requires_testing_data
 def test_anonymize(subject, dir_name, fname, reader, tmp_path, _bids_validate):
-    """Test writing anonymized EDF data."""
+    """Test writing anonymized data."""
     raw_fname = op.join(data_path, dir_name, fname)
 
     bids_root = tmp_path / "bids1"
@@ -3197,21 +3203,21 @@ def test_anonymize(subject, dir_name, fname, reader, tmp_path, _bids_validate):
     # handle different edge cases
     if subject == "emptyroom":
         bids_path.update(task="noise", session=raw_date, suffix="meg", datatype="meg")
-        erm = None
+        write_kw = dict(empty_room=None)
+    elif dir_name == "Brainvision":  # pretend it's EMG data
+        raw.set_channel_types({ch: "emg" for ch in raw.ch_names})
+        raw.set_montage(None)
+        bids_path.update(task="task", suffix="emg", datatype="emg")
+        write_kw = dict(empty_room=None, emg_placement="Measured")
     else:
         bids_path.update(task="task", suffix="eeg", datatype="eeg")
         # make sure anonymization works when also writing empty room file
-        erm = raw.copy()
+        write_kw = dict(empty_room=raw.copy())
     daysback_min, daysback_max = get_anonymization_daysback(raw)
     anonymize = dict(daysback=daysback_min + 1)
     orig_bids_path = bids_path.copy()
     bids_path = write_raw_bids(
-        raw,
-        bids_path,
-        overwrite=True,
-        anonymize=anonymize,
-        verbose=False,
-        empty_room=erm,
+        raw, bids_path, overwrite=True, anonymize=anonymize, verbose=False, **write_kw
     )
     # emptyroom recordings' session should match the recording date
     if subject == "emptyroom":
@@ -3225,7 +3231,8 @@ def test_anonymize(subject, dir_name, fname, reader, tmp_path, _bids_validate):
         assert _raw.info["meas_date"].year == 1985
         assert _raw.info["meas_date"].month == 1
         assert _raw.info["meas_date"].day == 1
-    assert raw2.info["meas_date"].year < 1925
+    year = 1986 if dir_name == "Brainvision" else 1925
+    assert raw2.info["meas_date"].year < year
 
     # write without source
     scans_fname = BIDSPath(
@@ -3237,7 +3244,12 @@ def test_anonymize(subject, dir_name, fname, reader, tmp_path, _bids_validate):
     )
     anonymize["keep_source"] = False
     bids_path = write_raw_bids(
-        raw, orig_bids_path, overwrite=True, anonymize=anonymize, verbose=False
+        raw,
+        orig_bids_path,
+        overwrite=True,
+        anonymize=anonymize,
+        verbose=False,
+        **write_kw,
     )
     scans_tsv = _from_tsv(scans_fname)
     assert "source" not in scans_tsv.keys()
@@ -3249,6 +3261,7 @@ def test_anonymize(subject, dir_name, fname, reader, tmp_path, _bids_validate):
         overwrite=True,
         anonymize=dict(daysback=daysback_min, keep_source=True),
         verbose=False,
+        **write_kw,
     )
     scans_fname = BIDSPath(
         subject=bids_path.subject,
@@ -3259,7 +3272,8 @@ def test_anonymize(subject, dir_name, fname, reader, tmp_path, _bids_validate):
     )
     scans_tsv = _from_tsv(scans_fname)
     assert scans_tsv["source"] == [Path(f).name for f in raw.filenames]
-    _bids_validate(bids_path.root)
+    if dir_name != "Brainvision":  # EMG not yet supported by validator
+        _bids_validate(bids_path.root)
 
     # update the scans sidecar JSON with information
     scans_json_fpath = scans_fname.copy().update(extension=".json")
@@ -3275,6 +3289,7 @@ def test_anonymize(subject, dir_name, fname, reader, tmp_path, _bids_validate):
         overwrite=True,
         anonymize=dict(daysback=daysback_min, keep_source=True),
         verbose=False,
+        **write_kw,
     )
     with open(scans_json_fpath) as fin:
         scans_json = json.load(fin)
@@ -3371,16 +3386,19 @@ def test_sidecar_encoding(_bids_validate, tmp_path):
 @testing.requires_testing_data
 def test_emg_errors_and_warnings(tmp_path):
     """Test EMG-specific error/warning raising."""
-    bids_root = tmp_path / "EDF"
-    raw_fname = data_path / "EDF" / "test_generator_2.edf"
+    bids_root = tmp_path / "EMG_errors"
+    raw_fname = data_path / "Brainvision" / "test_NO.vhdr"
     bids_path = _bids_path.copy().update(root=bids_root, datatype="emg")
-    raw = _read_raw_edf(raw_fname)
+    raw = _read_raw_brainvision(raw_fname)
     raw.set_channel_types({ch: "emg" for ch in raw.ch_names})  # HACK eeg → emg
-    raw = raw.pick(["emg"])  # drop misc
-    good_kwargs = dict(raw=raw, bids_path=bids_path, verbose=False)
+    good_kwargs = dict(raw=raw, bids_path=bids_path, verbose=False, overwrite=True)
     with pytest.raises(ValueError, match="`emg_placement` must be one of"):
         write_raw_bids(**good_kwargs, emg_placement="Foo")
-    with pytest.warns(RuntimeWarning, match="add `coordsystem.json` file manually"):
+    with (
+        pytest.warns(RuntimeWarning, match="BDF format requires equal-length data"),
+        pytest.warns(RuntimeWarning, match="Converting data files to BDF format"),
+        pytest.warns(RuntimeWarning, match="add `coordsystem.json` file manually"),
+    ):
         write_raw_bids(**good_kwargs, emg_placement="Other")
 
 
@@ -3399,7 +3417,6 @@ def test_convert_emg_formats(tmp_path, dir_name, fmt, fname, reader):
     bids_path = _bids_path.copy().update(root=bids_root, datatype="emg")
     raw = reader(raw_fname)
     raw.set_channel_types({ch: "emg" for ch in raw.ch_names})  # HACK eeg → emg
-    raw = raw.pick(["emg"])  # drop misc
     # test anonymization in one case too, for coverage
     if dir_name == "Brainvision":
         raw.anonymize()
@@ -3803,8 +3820,8 @@ def test_write_associated_emptyroom(_bids_validate, tmp_path, empty_room_dtype):
     assert meg_json_data["AssociatedEmptyRoom"] == expected_rel
 
 
-def test_preload(_bids_validate, tmp_path):
-    """Test writing custom preloaded raw objects."""
+def test_preload_errors(tmp_path):
+    """Test allow_preload error handling."""
     bids_root = tmp_path / "bids"
     bids_path = _bids_path.copy().update(root=bids_root)
     sfreq, n_points = 1024.0, int(1e6)
@@ -3814,25 +3831,45 @@ def test_preload(_bids_validate, tmp_path):
     raw.orig_format = "single"
     raw.info["line_freq"] = 60
 
+    shared_kwargs = dict(raw=raw, bids_path=bids_path, verbose=False, overwrite=True)
     # reject preloaded by default
     with pytest.raises(ValueError, match="allow_preload"):
-        write_raw_bids(raw, bids_path, verbose=False, overwrite=True)
+        write_raw_bids(**shared_kwargs)
 
     # preloaded raw must specify format
     with pytest.raises(ValueError, match="format"):
-        write_raw_bids(
-            raw, bids_path, allow_preload=True, verbose=False, overwrite=True
-        )
+        write_raw_bids(**shared_kwargs, allow_preload=True)
+
 
+@pytest.mark.filterwarnings(
+    warning_str["edfblocks"],
+    warning_str["emg_coords_missing"],
+    warning_str["converting_to_edf"],
+)
+@pytest.mark.parametrize(
+    "format,ch_type", (("BrainVision", "eeg"), ("BDF", "emg"), ("EDF", "seeg"))
+)
+def test_preload(_bids_validate, tmp_path, format, ch_type):
+    """Test writing custom preloaded raw objects."""
+    bids_root = tmp_path / "bids"
+    bids_path = _bids_path.copy().update(root=bids_root)
+    sfreq = 1024.0
+    info = mne.create_info(["ch1", "ch2"], sfreq, ch_type)
+    raw = mne.io.RawArray(np.empty((2, 100), dtype=np.float32), info)
+    raw.orig_format = "single"
+    raw.info["line_freq"] = 60
+    kw = dict(emg_placement="Measured") if ch_type == "emg" else dict()
     write_raw_bids(
         raw,
         bids_path,
-        allow_preload=True,
-        format="BrainVision",
         verbose=False,
         overwrite=True,
+        allow_preload=True,
+        format=format,
+        **kw,
     )
-    _bids_validate(bids_root)
+    if ch_type != "emg":  # TODO validator support for EMG not available yet
+        _bids_validate(bids_root)
 
 
 @pytest.mark.parametrize("dir_name", ("tsv_test", "json_test"))
diff --git a/mne_bids/utils.py b/mne_bids/utils.py
index f8509a083a..48ac30fdad 100644
--- a/mne_bids/utils.py
+++ b/mne_bids/utils.py
@@ -135,7 +135,7 @@ def _handle_datatype(raw, datatype):
     raw : mne.io.Raw
         Raw object.
     datatype : str | None
-        Can be one of either ``'meg'``, ``'eeg'``, or ``'ieeg'``. If ``None``,
+        Can be one of either ``'meg'``, ``'eeg'``, ``'emg'`` or ``'ieeg'``. If ``None``,
         `mne.utils._handle_datatype()` will attempt to infer the datatype from
         the ``raw`` object. In case of multiple data types in the ``raw``
         object, ``datatype`` must not be ``None``.
@@ -143,7 +143,7 @@ def _handle_datatype(raw, datatype):
     Returns
     -------
     datatype : str
-        One of either ``'meg'``, ``'eeg'``, or ``'ieeg'``.
+        One of either ``'meg'``, ``'eeg'``, ``'emg'``, or ``'ieeg'``.
     """
     if datatype is not None:
         _check_datatype(raw, datatype)
@@ -173,7 +173,7 @@ def _handle_datatype(raw, datatype):
             datatypes.append("nirs")
         if len(datatypes) == 0:
             raise ValueError(
-                "No MEG, EEG, iEEG, or EMG channels found in data. "
+                "No MEG, EEG, iEEG, EMG, or fNIRS channels found in data. "
                 "Please use raw.set_channel_types to set the "
                 "channel types in the data."
             )
@@ -182,8 +182,6 @@ def _handle_datatype(raw, datatype):
                 datatype = "meg"
             elif "ieeg" in datatypes and "meg" not in datatypes:
                 datatype = "ieeg"
-            elif "emg" in datatypes:
-                datatype = "emg"
             else:
                 raise ValueError(
                     f"Multiple data types (``{datatypes}``) were "
diff --git a/mne_bids/write.py b/mne_bids/write.py
index 3af0c3bf7a..8f81c30e3a 100644
--- a/mne_bids/write.py
+++ b/mne_bids/write.py
@@ -1351,7 +1351,15 @@ def _write_raw_edf_bdf(raw, bids_fname, overwrite):
     overwrite : bool
         Whether to overwrite an existing file or not.
     """
-    assert bids_fname.suffix in (".edf", ".bdf")
+    ext = bids_fname.suffix[1:].upper()
+    assert ext in ("EDF", "BDF")
+    if raw.info["meas_date"].year < 1985:
+        warn(
+            f"Attempting to write a {ext} file with a meas_date of "
+            f"{raw.info['meas_date']}. This is not supported; {ext} limits dates to "
+            "after 1985-01-01. Setting raw.info['meas_date'] to 1985-01-01."
+        )
+    raw.set_meas_date(raw.info["meas_date"].replace(year=1985, month=1, day=1))
     raw.export(bids_fname, overwrite=overwrite)
 
 

From 7d6b5760911b37ebe8a019bc839a58daa889aa0c Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Fri, 14 Nov 2025 14:44:03 -0600
Subject: [PATCH 23/25] fix warning match

---
 mne_bids/tests/test_write.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mne_bids/tests/test_write.py b/mne_bids/tests/test_write.py
index 09458e6363..35eab54773 100644
--- a/mne_bids/tests/test_write.py
+++ b/mne_bids/tests/test_write.py
@@ -105,7 +105,7 @@
         "ignore:Channel mismatch between .*channels\\.tsv and the raw data file "
         "detected\\.:RuntimeWarning:mne"
     ),
-    edf_date="ignore:.*limits dates to after 1985-01-01:RuntimeWarning",
+    edf_date="ignore:.*limits `startdate` to dates after 1985-01-01:RuntimeWarning",
 )
 
 

From ad30c6afb944088f71dacb9f7e31444e723455b7 Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Fri, 14 Nov 2025 15:37:16 -0600
Subject: [PATCH 24/25] add version guard on more tests

---
 mne_bids/tests/test_write.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/mne_bids/tests/test_write.py b/mne_bids/tests/test_write.py
index 35eab54773..b6dfc5277a 100644
--- a/mne_bids/tests/test_write.py
+++ b/mne_bids/tests/test_write.py
@@ -3207,6 +3207,7 @@ def test_anonymize(subject, dir_name, fname, reader, tmp_path, _bids_validate):
         bids_path.update(task="noise", session=raw_date, suffix="meg", datatype="meg")
         write_kw = dict(empty_room=None)
     elif dir_name == "Brainvision":  # pretend it's EMG data
+        pytest.importorskip("mne", minversion="1.10.2", reason="BDF export")
         raw.set_channel_types({ch: "emg" for ch in raw.ch_names})
         raw.set_montage(None)
         bids_path.update(task="task", suffix="emg", datatype="emg")
@@ -3388,6 +3389,7 @@ def test_sidecar_encoding(_bids_validate, tmp_path):
 @testing.requires_testing_data
 def test_emg_errors_and_warnings(tmp_path):
     """Test EMG-specific error/warning raising."""
+    pytest.importorskip("mne", minversion="1.10.2", reason="BDF export")
     bids_root = tmp_path / "EMG_errors"
     raw_fname = data_path / "Brainvision" / "test_NO.vhdr"
     bids_path = _bids_path.copy().update(root=bids_root, datatype="emg")
@@ -3894,6 +3896,8 @@ def test_preload_errors(tmp_path):
 )
 def test_preload(_bids_validate, tmp_path, format, ch_type):
     """Test writing custom preloaded raw objects."""
+    if format == "emg":
+        pytest.importorskip("mne", minversion="1.10.2", reason="BDF export")
     bids_root = tmp_path / "bids"
     bids_path = _bids_path.copy().update(root=bids_root)
     sfreq = 1024.0

From 14f4a71b0cbd8174fa5663b2300f2004e271edaf Mon Sep 17 00:00:00 2001
From: Daniel McCloy <dan@mccloy.info>
Date: Fri, 14 Nov 2025 15:55:31 -0600
Subject: [PATCH 25/25] fix dumb

---
 mne_bids/tests/test_write.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mne_bids/tests/test_write.py b/mne_bids/tests/test_write.py
index b6dfc5277a..7c00ba0b82 100644
--- a/mne_bids/tests/test_write.py
+++ b/mne_bids/tests/test_write.py
@@ -3896,7 +3896,7 @@ def test_preload_errors(tmp_path):
 )
 def test_preload(_bids_validate, tmp_path, format, ch_type):
     """Test writing custom preloaded raw objects."""
-    if format == "emg":
+    if ch_type == "emg":
         pytest.importorskip("mne", minversion="1.10.2", reason="BDF export")
     bids_root = tmp_path / "bids"
     bids_path = _bids_path.copy().update(root=bids_root)