delay first serial write to allow host setup time #7041
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dhalbert
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Tested on picow and waveshare_esp32s2_pico. This issue seems fixed. |
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@bill88t Great! Thanks for testing. |
jepler
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Oct 12, 2022
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Fixes #6892 and other cases in which serial output (usually USB output) is fed back into the REPL input, as noted on Linux. (@bill88t take note.)
@jepler's diagnosis of this is that serial terminal programs on Linux first open the serial channel with "echo mode" on, in which serial output is echoed back to the serial input. They then immediately turn echo off with an
ioctl(), but there is a race condition in which one or more characters may get echoed before the echo gets turned off.This PR adds 50 ms of delay before the very first write after the serial channel (USB or console UART) is available. I also tested with 100ms, but 50ms seems to be enough.
@jepler Could you test this on the nRF52840, which exhibits this problem even without the status bar? I could not reproduce it on my end, but on the other hand you had more trouble reproducing the status bar problem. Thanks.
@hathach this appears to be what we were trying to understand late last night (for you).