Sending 0377 via KL8JA
bqt at update.uu.se
Mon Jan 19 07:05:59 CST 2015
This sounds like a typical TCP/IP telnet issue.
The telnet protocol (there actually is one) requires that all 377(8) be
doubled. More properly I should perhaps say the NVT protocol used by telnet.
On 2015-01-19 06:39, Kyle Owen wrote:
> I am noticing something odd in SimH when sending a 0377 (all ones)
> character. It seems to be duplicating the byte. I haven't read anything
> regarding this behavior. I'm away from my hardware PDP-8 at the moment, so
> I can't confirm that this is not the behavior that I would experience on
> the real thing.
> Here's how I reproduced it:
> CLA OSR
> JMS SEND
> JMP 200
> SEND, 0
> JMP .-1
> JMP I SEND
> at ttix 2222
> set ttox0 8b
> load test.bin
> br 200
> d sr 0377
> Run 'nc localhost 2222 | od -to1' in a terminal, then 'go 200' and
> repeatedly press 'c', seeing how many times it takes to generate a line of
> characters in 'od'. Then, 'd sr 0376' and confirm that it takes twice as
> many presses, indicating half as many characters being sent per TLS
> instruction with the latter.
> Can anyone else confirm this for me?
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