On Thu, 6 Jan 2005, Dwight K. Elvey wrote:
In the past when I wanted a non-block binary
transfer,
I often had some value that I used as an escape character.
I'd choose a low frequency value to improve throughput.
It is simple, If you want to send a command value, you
send the escape character, first. If you just wanted the escape
character, you'd send it twice. For 8 bit data, you
had 255 commands. EOF could be one of those.
It makes a simple protocol that is easy to implement in
code.
A perfectly good and simple protocol for a simple serial interface (i.e.
2 or 3 wires max). But I submit that the BREAK signal could have been
used, which is inline and is part of the RS232 spec for this very reason.
Anyway, dead horse is now a pile of fur. The ants are already back in
their hole and the flies have long since flown away.
--
Sellam Ismail Vintage Computer Festival
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