Re: [Simh] pdp11 - console input with high bit set

2020-07-25 Thread Rich Alderson
> From: Johnny Billquist > Date: Sat, 25 Jul 2020 00:58:08 +0200 > I would have to disagree with that. All older PDP-8 software is > definitely using MARK parity, not EVEN. Both on input and output. > (Sortof annoying if you aren't expecting it.) > The ASR33, as configured by DEC, was normally

Re: [Simh] pdp11 - console input with high bit set

2020-07-25 Thread Clem Cole
On Sat, Jul 25, 2020 at 2:29 PM Timothe Litt wrote: > How often you got parity errors was a function of modem generation and > line quality - acoustic couplers from your house in the country were good > for frequent parity - and mult-bit - errors. > Amen ... I remember those days - calling to a G

Re: [Simh] pdp11 - console input with high bit set

2020-07-25 Thread Timothe Litt
On 25-Jul-20 13:47, Paul Koning wrote: >> But by the mid to late 70s, i.e. with the glass TTY it started to fall from >> favor. I don't know why, but I would suspect this was because dedicated >> lines started to supplant telephone circuit-based connections and single-bit >> error detect was

Re: [Simh] pdp11 - console input with high bit set

2020-07-25 Thread Paul Koning
> On Jul 24, 2020, at 5:57 PM, Clem Cole wrote: > > ... >> If you set your UART for 8 bits with parity, it would send 11 bits total: >> start, 8 data, parity, stop. > Yep ... you are correct that is exactly how the hardware works. mei culpa. > Although, if we are going to get specific.