What are you using as a TU? I was toying with the idea a few years ago of building a minimal RTTY interface for my T102 with a couple tone decoder ICs, but I ended up working on MFORTH instead.
On May 6, 2026 7:22:24 AM UTC, Peter Noeth <[email protected]> wrote: >B9, > > I was working on a RTTY decoder, and I was using the BASIC program " >RTTY.BA (https://ftp.whtech.com/club100/tel/rtty.ba)" and "RTTY.DO ( >https://ftp.whtech.com/club100/tel/rtty.do)" as a guide. This program will >receive a serial data string on the RS232 port from the "Terminal Unit" >(which converts two alternating audio tones to digital "1" and "0" levels. >It can also send data to the "Terminal Unit" to change the digital "1" and >"0" levels to the same two audio tones. > > I wanted to make a program only for receive. I was using the "RTTY" >program to understand how the PIO timer, which is used for the UART baud >clock, was set to make the UART work at the odd speeds that were used "in >the old days" by the BAUDOT encoded teletypes. > >John, > > The "Inside the Model 100" book by Carl Oppedahl does not list FF8Dh. The >last address noted is FF8B which is noted as "address of baud rate". > > I have seen the notation in the "Covington ROM Map", and I believe this >is where Ken got the same notation in his ROM listing (in his personal >library on the Club100 page). But it doesn't seem that Robert Covington >ever wrote a book on the Model 100. For such a detailed ROM listing, I >would have expected that he would have. He must have been involved in >accessories for the Model 100 in some capacity. > >Regards, >PeterN
