Good morning all,
I'm looking to generate sounds with the MIC port of the ZX81 but I can't find any information on the subject ...
I read that it was port 255 which was used for the MIC output. So I tried in assembler with the OUT instruction of the Z80 to pass the port 255 to 255 (since I do not know the exact bit which is used) then then to zero with a deceleration loop so as to generate a signal d 'about 3khz but I got no signal on the MIC output ...
If someone has already tried to manipulate the MIC output I would be interested to have some information
Thanks in advance to all
Sound MIC output
Re: Sound MIC output
Welcome to our forums.
Have a look at mastering machine code on your zx81 chapter 12
http://www.users.waitrose.com/~thunor/m ... ter12.html
Kind regards Paul
Have a look at mastering machine code on your zx81 chapter 12
http://www.users.waitrose.com/~thunor/m ... ter12.html
Kind regards Paul
In theory, there is no difference between theory and practice. But, in practice, there is.
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Re: Sound MIC output
Good-morning Paul,
Thanks a lot for your help !
I was able to download the little program from chapter 12 which works very well and generates nice notes on the MIC output of the ZX81
I will now be able to study the program closely and then do my own assembly routines.
Again thanks to you
Thanks a lot for your help !
I was able to download the little program from chapter 12 which works very well and generates nice notes on the MIC output of the ZX81
I will now be able to study the program closely and then do my own assembly routines.
Again thanks to you
Re: Sound MIC output
You are welcome.
In theory, there is no difference between theory and practice. But, in practice, there is.
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Re: Sound MIC output
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
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ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.