Re: 6502 to 7501/8501 converter

From: Gerrit Heitsch <*gerrit_at_laosinh.s.bawue.de*> Date: Sun, 17 Jun 2018 10:58:31 +0200 Message-ID: <d6a77305-1076-87f6-aa74-beaf6e42671a@laosinh.s.bawue.de> · gerrit_at_laosinh.s.bawue.de

On 06/17/2018 09:18 AM, Jim Brain wrote:
> I think someone was wanting this: https://github.com/go4retro/Fake7501

Under 'Theory', you wrote the following:

The 6502 address, data, and r/w lines are fed through the CPLD so they 
cna be optionally tri-stated, and the on-board PIO port bits 0-6 are 
emulated.

The 7501/8501 has Bit 0-4 and 6 and 7 on the PIO port, Bit 5 is the 
missing one. This makes it easy to use BIT commands when reading data.

  Gerrit