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Subject: serial driver
Date: Thu, 06 Mar 1997 21:48:09 -0800
From: Steven Wallace <swallace@ece.uci.edu>
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I have noticed a problem with the sio driver.

When receiving data, it goes into a buffer until it is read by read(), right?

Well, I am losing data because after DTR is dropped, up to 16 bytes sent
BEFORE DTR are lost or destroyed, so read() is not picking this up.
Even though DTR is dropped, that does not mean all data received in any
buffer is not valid at this point, but only data received AFTER.
So even if a read() call is actually called after DTR is dropped,
it should still return any remaining bytes.

Note:  As a result, up to 16 bytes can be lost.  I have a 16550A chip
so the driver might not be reading remaining bytes in its buffer.
I am using 2.2R.

Please let me know what the deal is.

Thanks,

Steven