I spent hours this morning (insomnia caused by excitement) with a logic analyzer and now I've run the demos in EO I think I know why my board remains silent...
The Zon-X manual states that ports $0F & $CF are used for IO. So why-oh-why are people using $DF? Is there another AY board out there which uses this port? Is this compatible with the Zon-X board? I remember Siggi had to modify his original Zon-x to work with this address - Siggi?
When I built the ZXpand IO equations I expected $CF to be used. Unlike most boards ZXpand decodes IO addresses fully - IE it uses all the 7 address bits in the comparison. This means it won't trigger against $DF. It's my intention that I won't release new GAL code as it's technically not necessary - we need to ensure that all players have the option to be poked or configured to use 'strict' addressing...
I'll get busy with some poking at lunchtime and see what comes out.
0xDF and 0x0F (modified zonX and projects from papers)
0xCF and 0x1F (original zonX)
0xCF and 0x0F (from zonX manual)
0xDF and 0x1F (theoretically possible, maybe non relevant, but accepted by a new designed board from Sascha2000)
This is what is found to be relevant for soundmodules, I am afraid thats all used in some software, some of the games where we have to find out which adresses to poke...
Sascha2000 goes the other way and accepts all of these adresses to be shure every program will work.
see http://forum.tlienhard.com/phpBB3/viewt ... 3267#p3266
as a reference
In theory, there is no difference between theory and practice. But, in practice, there is.
sirmorris wrote:
The Zon-X manual states that ports $0F & $CF are used for IO. So why-oh-why are people using $DF? Is there another AY board out there which uses this port? Is this compatible with the Zon-X board? I remember Siggi had to modify his original Zon-x to work with this address - Siggi?
