Quote:
Originally Posted by ortek_service
And it's also possible that a 6522 VIA may also work, if these are pin-compatible (will need to check), as the 6522 is really an enhanced 6520 with extra registers / timers etc.
- With the 6520 falling out of use and the 6522 much more widely used (even if the extra timers etc. in it were not actually required)
It seems the PET was the main user of the 6520, with commodore moving onto the 6522 in the VIC-20, before using their own 'custom' 6526 CIA for the C64 as they were rather-keen in keeping the MOS fab busy.
|
The 6522 is a completely different chip. The 6522 has 16 registers, the 6520/21 only 4. The pinout is different. The 6520 and 6521 are equivelents however.
The PET has 6520's and a 6522 for the user port.