Refactor DS18B20 Temperature Conversion Time Handling#1824
Open
echavet wants to merge 2 commits intorwaldron:mainfrom
Open
Refactor DS18B20 Temperature Conversion Time Handling#1824echavet wants to merge 2 commits intorwaldron:mainfrom
echavet wants to merge 2 commits intorwaldron:mainfrom
Conversation
Currently, the DS18B20 driver uses a fixed delay of 1 millisecond (board.io.sendOneWireDelay(pin, 1);) after requesting each sensor to perform a temperature conversion. However, the DS18B20 datasheet specifies that a conversion actually takes up to 750 milliseconds. This misalignment could potentially lead to inaccuracies when reading from multiple DS18B20 sensors simultaneously, particularly if the requested frequency (options.freq) is shorter than the time required for a temperature conversion. Additionally, it's important to note that the implementation of the delayTask function on the Firmata side is not fully functional and relies on the inclusion of a "FirmataScheduler" module, which merely adds processor cycles and does not provide a true delay mechanism. rwaldron#1823
Support for changes to the DS18B20 Thermometer Driver: - Removed the test for the call to `sendOneWireDelay` as it is no longer necessary. - Modified the delays to account for the 750ms delay.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Currently, the DS18B20 driver uses a fixed delay of 1 millisecond (board.io.sendOneWireDelay(pin, 1);) after requesting each sensor to perform a temperature conversion. However, the DS18B20 datasheet specifies that a conversion actually takes up to 750 milliseconds.
This misalignment could potentially lead to inaccuracies when reading from multiple DS18B20 sensors simultaneously, particularly if the requested frequency (options.freq) is shorter than the time required for a temperature conversion. Additionally, it's important to note that the implementation of the delayTask function on the Firmata side is not fully functional and relies on the inclusion of a "FirmataScheduler" module, which merely adds processor cycles and does not provide a true delay mechanism.
#1823