I'd be more than happy to get back to the topic. My aim here is not to try to change your usage, BDD, but to make it clear - as you don't - that it's only one of two usages.
WeeMan wrote:
My idea is to receive an audio RadioTeleTypeY RTTY signal into the host machine, demodulate the received BAUDOT code, convert the received character to ASCII and display the DECODED characters onto the screen. It would probably be easier if I had an actual 6502 machine like a BBC Master/Acorn or Oric to code with but at present using an IDE and emulator created for game development.
As noted, any open source emulator offers at least the possibility that you could extend it, to model some component which you would have in your proposed system and which isn't standard. Or, if not actually modelling an ADC, at least modelling the data which the ADC produces and which the 6502 system has to read.
Quote:
I see that I have to create a translation table to change the received characters from BAUDOT to ASCII and then use sys calls for screen display etc but its the actual input and conversion to bytes that I am sketchy about.
A great deal depends on the hardware you use. Hoglet's setup
hoglet wrote:
There's another Stardot thread that might be of interest as well:
Hoglet's Past Projects #2 - the RTTY receiverIn this project the demodulation of the RTTY signal is done in hardware, leaving the computer just to decode the serial bitstream.
produces a serial bitstream. So you're looking at a hardware UART to accept that serial bitstream, or a bit-banged software UART receiver. Such things have been done before - the lower the datarate, the easier this job is. If you start with a web search of "uart start bit sample" or similar, you'll see lots of articles with diagrams. Once you understand the principles, you can tackle the coding.