Re: Linux serial port dropping bytes

CBFalconer wrote:
<snip>
I left the whole thing unsnipped. The time has come for me to
crave forgiveness. I think I have been afflicted with age or
something. The bits/persec crowd are absolutely correct, and I am
wrong.


I don't think you need forgiveness - you just made a mistake.

So that leaves the real problem handling throughput of
approximately 1 char each 10 microsec.


You need to handle an *average* of 1 character per 10 us. But the cost of handling each character is peanuts - even if the UART is on a slow bus, you should be able to read out characters at something like 20 per us. The cost is in the handling of the interrupt itself - context switches, cache misses, etc. That's why you use a UART with a buffer - it takes virtually the same time to read 128 bytes out the buffer during one interrupt, as to read 1 byte from the buffer during the interrupt. So if you've set your UART to give an interrupt every 100 characters, you get an interrupt every ms and read out a block of 100 characters at a time.
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