Impressive project you have there. Thanks for posting the additional information. I have been adding comments to your code to help me understand what you are doing, and while I found where you disabled the Z80 RD/WT (# 3 on your description) I could not find anywhere it was re-enabled (#11). Does it need to be enabled (I'm pretty sure it does), and where in the code is that done?
Yes the RD/WT buffer must be enabled to allow the Z80 to operate. The Z80 RD/WT buffer is enabled in the "Z80_Reset" function found in the "Z80Cntrl.spin" file.
mov OUTA, #0
mov DIRA, BaseDirRegMsk
' CPU reset is active, clock is low, and the RD/WT line buffer is enabled.
Thanks for posting that. Could not find it in the file I was adding comments to, but it was there in the original download. Four lines were missing so I guess I must have inadvertently erased them at some point.
Comments
Impressive project you have there. Thanks for posting the additional information. I have been adding comments to your code to help me understand what you are doing, and while I found where you disabled the Z80 RD/WT (# 3 on your description) I could not find anywhere it was re-enabled (#11). Does it need to be enabled (I'm pretty sure it does), and where in the code is that done?
Yes the RD/WT buffer must be enabled to allow the Z80 to operate. The Z80 RD/WT buffer is enabled in the "Z80_Reset" function found in the "Z80Cntrl.spin" file.
mov OUTA, #0
mov DIRA, BaseDirRegMsk
' CPU reset is active, clock is low, and the RD/WT line buffer is enabled.