cnlohr / espusb

Software-only ESP8266 USB Device
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Consider false-ACKing for full-speed experimentation #28

Open cnlohr opened 7 years ago

cnlohr commented 7 years ago

The ESP does have the I2S bus which can read the I2S pin very quickly. I thought that would be impossible to use because of the latency incurred. @scanlime pointed out in Twitter https://twitter.com/scanlime/status/814213365715193856 that we could just send a bogus ACK and keep moving.

The example exists in the propeller example here: https://github.com/scanlime/propeller-usb-host/commits/master/usb-fs-host.spin

I am trying to think about possible schemes to watch for an SE0 flag and immediately send an ACK. I think it may need external hardware, though.