Hello
There is that interesting background thinking noise the cpc464 comes with and what makes the cpc somehow special.
An explanation was given in the magazine AmstradComputerUser02-1084.pdf on page 36 (attached).
I still have questions:
* How is that implemented technically?
* can this be amplified a little more?
* Are there emulators adressing this "thinking" sound?
Thanks
RST
Hi maschinist,
still laughing at the "How is it implemented question"!! (http://www.cpcwiki.eu/forum/Smileys/SoLoSMiLeYS1/cheesy.gif) It's not "implemented" , it's a side-effect of the crap amplifier design, which is neither isolated nor screened.
Bryce.
QuoteIt's not a fault. It's a feature
Good one.
Alright, thank you for clearificaton. ;) I got it.
Heh, I remember reading that ACU reply... It's delivered in a quite serious manner so I bet lots of users fell for it back then :D
maybe its my imagination, but the audio line out is a lot cleaner than some later PCs and laptops, i never used the internal speaker
could be emulated by sending upper addres + lower address bus + data bus to /dev/dsp? :)
just a thougth...
Simple to emulate:
Emulating CPC 464 designed background noise - YouTube (https://www.youtube.com/watch?v=8VCm7HZP0GU)
Wow - that is awesome.
This emulation sounds like on a real vintage machine. 8)
Thumbs up!
Maybe the only difference to the real cpc464 is maybe the 50 Hz.
When I switch on my >>GT 64<< my desk is vibrating @50...
To emulate it:
Just check the memory part in your emulator source...
Where your emulated CPC memory reads bytes (usually a code like this:
public int readByte(int address) {
int result = mem[readMap[address >> 13] + (address & 0x1fff)] & 0xff;
return result;
}
Just send the read value with volume down to an audio device:
Use an Integer like bytenoise and feed it before you return the result:
public int readByte(int address) {
int result = mem[readMap[address >> 13] + (address & 0x1fff)] & 0xff;
bytenoise = (result & 0xff) >> 6;
return result;
}
I added this (lousy) emulation on JavaCPC Applet...
http://cpc.devilmarkus.de (http://cpc.devilmarkus.de) (All old-cpc games and demos will feature this now)
Numberpad + key: enable background noise
Numberpad - key: disable background noise
Heheh silliest, funniest thing in a long time :D