been looking into this, got a picoscope recently and remembered it does i2c decoding so thought i’d try that. confirmed first it decodes properly with orca remotes. then tried reading CV from ansible. no freezing when triggering manually (red is SDA, blue is SCL):
^ this is the last part, the 2nd byte in the ansible response to a write request which is not shown here. it returns data properly (in this case 0F). then i tried triggering it repeatedly by using WIN+1 to trigger a script and holding the buttons so it would keep calling it, and in a few seconds it froze. the read request from TT looks fine, as does the first byte sent by ansible but on the 2nd byte here is what happens:
looks like in the first graph it properly lets SDA go high after SCL is high to signal the end of transmission but in the 2nd one something pulls SDA back down and it stays down.
i’ll try more scenarios tomorrow - let me know if you want me to check anything specifically, thought i’d post this first in case it proves helpful. i’ve been reading up on i2c and looking at the code over the holidays and so far it does seem to be some sort of race condition… but that’s just a SWAG at this point.
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