terriblefire wrote: ↑Fri Oct 08, 2021 2:25 pm
Well depending on how well this all works we might be able to ditch the EPROM and save a few £££.
If I can talk to bus directly, this would open quite few possibilities.
On the other hand if this was possible why no one done it before?
Anyway it is worth trying, winters in Scotland are long
Do not trust people. They are capable of greatness.
~ Stanislaw Lem
arkadiusz.makarenko wrote: ↑Fri Oct 08, 2021 3:34 pm
If I can talk to bus directly, this would open quite few possibilities.
On the other hand if this was possible why no one done it before?
Anyway it is worth trying, winters in Scotland are long
The CPLD is in charge of everything on the bus. It generates clocks for everything too. Every chip talks to it. The ram even flows through it to save paying for buffers. So the ARM could have its own little interface to service up address / mapper ranges etc.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."
arkadiusz.makarenko wrote: ↑Fri Oct 08, 2021 3:34 pm
If I can talk to bus directly, this would open quite few possibilities.
On the other hand if this was possible why no one done it before?
Anyway it is worth trying, winters in Scotland are long
The CPLD is in charge of everything on the bus. It generates clocks for everything too. Every chip talks to it. The ram even flows through it to save paying for buffers. So the ARM could have its own little interface to service up address / mapper ranges etc.
Any chance of an educational Verilog snippet on how to properly implement buffers in a CPLD? Any time I've attempted that in the past I've end up creating latches, which causes the synthesis tool to get angry!
arkadiusz.makarenko wrote: ↑Fri Oct 15, 2021 3:31 pm
@terriblefire
May I ask what must requirements do you have for ARM firmware on this board?
Usb keyboard, and gameports is a must.
ROM emulation if we can directly talk to the bus?
Edit
I am just thinking if I can do any more prep work or I can wait and jump in when Rev1 arrives.
Actually just keyboard. Maybe gameports too.
———
"It is not necessarily a supply voltage at no load, but the amount of current it can provide when touched that
indicates how much hurting you shall receive."