[LEDE-DEV] Serial data getting lost - bug or a feature?
nop at nop.com
Fri Oct 20 08:09:27 PDT 2017
On 2017-10-18 Wed, at 06:32, Valent Turkovic <valent at otvorenamreza.org> wrote:
> So if wifi is active, in sta mode but not associated to AP then serial
> communication is having issues and is loosing characters when
> receiving them.
Regardless of this poor behavior, I think you're going to regret it eventually if you don't have some kind of checksum and retransmit logic--implying you're also doing framing. Async serial lines can be tricky, and have non-zero bit error rates. And the framing mechanism needs to be resilient against incomplete packets (meaning, bytes dropped between transmitter and receiver).
Newline-separated ASCII records with a hex CRC are not the worst idea, but you need to deal with the situation where a newline gets lost, or you get trash or fewer bytes than you needed. I've used YMODEM before for bulk data.
Note that the Arduino Yún uses packets.
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