BEL constant in MAINDEC-8E-D0AB-PB

tony duell ard at
Thu Aug 18 10:57:44 CDT 2016

> I've been running and looking at the PDP-8/E INSTRUCTION TEST 1. And it
> is supposed to write the BEL (07) character after each round of passed
> tests. However the code loads and outputs the constant "0207", which is
> 07 with the eigth bit set. I think the 8/E serial interface outputs all
> eight bits in this case?
> I suppose a real ASR-33 would ignore the eight bit?
> Why does the code not load 07?

I would guess it is sending it as 7 (data) bits and even parity. 


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