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monome / ansible

http://monome.org/docs/ansible
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ansible: usb connect timing lag #23

Closed tehn closed 4 years ago

tehn commented 7 years ago

investigate timing glitch on usb connect

audionerd commented 5 years ago

i’ve noticed this when ansible is clocked externally. connecting a grid (via switch) causes kria to freeze and miss a beat.

csboling commented 4 years ago

Sounds like this has been investigated some, the search is still on for older discussion of this.

scanner-darkly commented 4 years ago

found it:

https://llllllll.co/t/teletype-3-feature-requests-and-discussion/16219/281 https://llllllll.co/t/teletype-3-feature-requests-and-discussion/16219/285 https://llllllll.co/t/teletype-3-feature-requests-and-discussion/16219/286

the experimental fix for it was commenting out this delay:

https://github.com/monome/libavr32/blob/master/src/usb/ftdi/uhi_ftdi.c#L194

not sure what's the purpose of that delay (to let the rest of initialization happen properly probably?) and whether removing it fixes it for some grids but breaks it for some others.