Well bu**er me sideways with a pitch-fork!
For the life of me I couldn't work out why my Mockingchick board wasn't working. As one last test before I went through another redesign, having re-re-re-checked my version against every other schematic I could find, I wrote Sweet Micro's test disc over the supposedly Mockingboard enabled copy of Zaxxon I had been using and...
...It works!!! Ooo, my ears. The last because I had it plugged in to the portable amp I use with the band with the volume right up in case there was any sign of life.
So there you go. I'm not (quite) as stupid as I thought. (Bl**dy Zaxxon!)
Things to check:
-why does the computer lock up after the first demo screen? (I think because my board has no speech support)
-Is it truly stereo, and are the channels the right way round?
-does the amplified out work, and as expected shut off with a jack in the line out?
-does the motherboard audio mixing work, without pushing it in to mono? (Already spotted a mistake here but I think I only need to change a couple of components to fix)
-have I got the motherboard / Mockingchick mixing levels about right? (I guessed this but now I can hopefully test it)
As a nice bonus it's working with a 7404 rather than the 7505 logic I feared it might need. Not a Biggie but the former is much cheaper and easier to get hold of than the latter. I'll probably try some WDC 6522's at some point to see if they work too - the new WDC IC's don't work quite the same as the good old R6522P's, something to watch out for when making devices using this chip.
Pretty darn pleased to say the least!
For the life of me I couldn't work out why my Mockingchick board wasn't working. As one last test before I went through another redesign, having re-re-re-checked my version against every other schematic I could find, I wrote Sweet Micro's test disc over the supposedly Mockingboard enabled copy of Zaxxon I had been using and...
...It works!!! Ooo, my ears. The last because I had it plugged in to the portable amp I use with the band with the volume right up in case there was any sign of life.
So there you go. I'm not (quite) as stupid as I thought. (Bl**dy Zaxxon!)
Things to check:
-why does the computer lock up after the first demo screen? (I think because my board has no speech support)
-Is it truly stereo, and are the channels the right way round?
-does the amplified out work, and as expected shut off with a jack in the line out?
-does the motherboard audio mixing work, without pushing it in to mono? (Already spotted a mistake here but I think I only need to change a couple of components to fix)
-have I got the motherboard / Mockingchick mixing levels about right? (I guessed this but now I can hopefully test it)
As a nice bonus it's working with a 7404 rather than the 7505 logic I feared it might need. Not a Biggie but the former is much cheaper and easier to get hold of than the latter. I'll probably try some WDC 6522's at some point to see if they work too - the new WDC IC's don't work quite the same as the good old R6522P's, something to watch out for when making devices using this chip.
Pretty darn pleased to say the least!
Grr, bl**dy Zaxxon, grumble
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