Re: Events on Serial port

Derek wrote, On 03.07.2008 23:02:

I'll take at look at these suggestions at work next week, I have amore
pressing problem in that the polling version that works fine under
linux dosn't under windows.
It seems a write over the serial port is screwwing things up some
where. I have to find out what this issue is before I can get any
further.

Write issues: Many people are not aware, that a non-blocking channel means non-blocking reads *_and writes_* (this was different for Windows-Tcl before 8.4).
Non-blocking writes means, that your [puts $chan] returns immediately buffering the data for background write *_at full baud speed_*. A slower receiving hardware may have problems with those writes.
[fconfigure $chan -queue] opens alternatives to you:
(A) Blocking channel, polling [fconfigure $chan -queue] in an after-script until the expected number of bytes have been received.
(B) Non-blocking channel, waiting for the output bytes to be sent after each write operation.
.

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