only channel 1 working for me under macOS and linux

[jluke1]

Looks like a very impressive project but what have I done wrong ?
Have breadboarded pico 1 with 10k resistor and push button.
Channel 1 works as expected but channels 2-8 always return 0 even with 10k pull-up resistor.
Measures 2.75V on scope at pin.

Have tried versions 5 and 6 and x86 and arm on different computers, and virtual box for linux.
Same result on all. Have not been able to load the kicad .sch file, gives error line 7.

What are other peoples experiences under macOS.

Regards
John Luke

[gusmanb]

To me that sounds more like an error in the hardware. Which firmware have you flashed? Also, can you do a screenshot of your capture settings?

[jluke1]

Firmware-LogicAnalyzer-5.1.0.0-PICO.uf2 logic-analyzer-firmware_v6.0.0_BOARD_PICO.uf2 Using logicanalyzer from all-in-one_6.0.0.1-linux-arm64.zip all-in-one_6.0.0.1-osx-arm64.zip all-in-one_6.0.0.1-osx-x64.zip LogicAnalyzer-5.1.0.0-osx-arm64.zip LogicAnalyzer-5.1.0.0-osx-x64.zip on different MacBook airs x64 and arm64 Regards John Luke

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On 22 Mar 2025, at 3:51 AM, Agustín Gimenez Bernad ***@***.***> wrote: To me that sounds more like an error in the hardware. Which firmware have you flashed? Also, can you do a screenshot of your capture settings? — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[gusmanb]

That must be a problem in the hardware for sure... Just in case, send a screenshot of the capture settings. Also, are you using an rp2040 or rp2350?.

Btw, channels don't map 1:1 to GPIOs, check the channel definitions in the firmware

[jluke1]

rp2040 early model. I have rp2350s but have not soldered in pins yet. Am hoping to wire wrap this up a as dedicated S100 bus monitor. Next test is to try with 2350. Can now run kicad I have only wired pins 1 and 2 together no resistor diode or ground connection. Regards John Luke

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On 22 Mar 2025, at 4:24 AM, Agustín Gimenez Bernad ***@***.***> wrote: That must be a problem in the hardware for sure... Just in case, send a screenshot of the capture settings. Also, are you using an rp2040 or rp2350?. Btw, channels don't map 1:1 to GPIOs, check the channel definitions in the firmware — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[beergut]

Firstly, what a wonderful project. Thank you @gusmanb !!! I am having the same issue here and I am using the latest version.

LogicAnalyzer version: all-in-one_v6.0.0.0-osx-arm64
Firmware version: logic-analyzer-firmware_v6.0.0_BOARD_PICO.uf2 running on a standard RP2040 Pico board.

Model Name: MacBook Air
Model Identifier: Mac14,2

Despite facing many issues running it on MacOS 15.5, I managed to get LogicAnalyzer started using command-line.

However, trying to capture some traces (to decode i2c), I found that only 1 channel was capturing.

My Capture settings as below:

I even followed the Wiki to short the Trigger pins (#1 and #2) before downloading the uf2 file into the Pico.

Some help is appreciated.

[gusmanb]

Ok, check a couple of things. First, I understand that you aren't using a board because of the comment of shorting the pins, so ensure that all connections are done properly, protoboards can be a nightmare of bad conectivity.

Next, try to swap SDA and SCL and check if still you capture data on channel 1.

Finally try to place a wire between +3v3 and channel 3 and see if it is shown as high.

Also, for I2C capture you should use a faster clock, if the I2C is operatin at high speed (400Khz) and you capture at 400Khz you will miss all the data in SCL. Try to capture at 1Mhz at least.

[beergut]

For now, I am using a bare Pico H board with Pin #1 and #2 shorted, and connect pin 3,4,5 to a PicoBricks project. The I2C is wired to the mini OLED display.

I already tried swapping SDA and SCL, but no signs of any signal other than channel #1.

Thank you for the suggesting the clock. I shall run it on 1MHz and report back.

I was curious to know how did the pervious user who started this topic solving his problems?

[beergut]

One thing I did not ask:

Does using just the Pico H works? Maybe I am missing something.

Thank you.

[gusmanb]

Uh.... Pin 3 on the pico is GND...

I think that what you are seeing is not SCL but SDA... That makes sense, you are connecting SCL to ground and SDA to channel 1...

[beergut]

Oh yes. My mistake. Pin 3 is actually ground. I was using pin 4 5 6 Best regards, Albert

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On Tue, Jul 15, 2025 at 12:28 Agustín Gimenez Bernad < ***@***.***> wrote: Uh.... Pin 3 on the pico is GND... [image: Raspberry pico pinout] <https://user-images.githubusercontent.com/4086913/221229250-51e03a76-2e01-48cc-a218-62fd21a8fbfb.png> I think that what you are seeing is not SCL but SDA... That makes sense, you are connecting SCL to ground and SDA to channel 1... — Reply to this email directly, view it on GitHub <#223 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAUGIRPFC3AJ7O5LTBDOT33IR7NBAVCNFSM6AAAAABZQLVIDWVHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTGNZWGAYDGOA> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.*** com>

[beergut]

Dear @gusmanb

Thank you for your patience and guidance. I have now done an extensive tests based on your suggestion, as it turns out 2 of my probe cables (Brand NEW) have discontinuity. So, whichever channel I go to, there is absolutely nothing.

So, I thought I use another cable for Ch 3 and Ch 4. Whalla ... signal comes out.

Thank you again.

Working happily decoding I2C.

My Capture Set Up

[gusmanb]

No worries at all, I'm glad that you solved it :)