Re: Strange 8255 behavior

From: Gerrit Heitsch <*gerrit_at_laosinh.s.bawue.de*> Date: Tue, 12 Jun 2018 19:08:49 +0200 Message-ID: <9369d15f-58cb-ce9b-e90f-72c593d0ed41@laosinh.s.bawue.de> · gerrit_at_laosinh.s.bawue.de

On 06/12/2018 07:06 PM, Mia Magnusson wrote:
> Den Tue, 12 Jun 2018 17:44:57 +0200 skrev groepaz@gmx.net:
>> Am Dienstag, 12. Juni 2018, 17:05:20 CEST schrieb Mia Magnusson:
>>> I can't remember which versions, but at least some version of the
>>> CIAs can only be used as one of the two CIA's in a C64. Using it as
>>> the other CIA causes keyboard problems.
>>
>> no, both can be (and are commonly) used in either position
> 
> Well, there are some revision of the CIA that only work in one
> position. I'll have to check the exact label of it.

You sure you're not talking about using a 8520, meaning a CIA meant for 
the Amiga, in a C64?

Any 6526 (*) or 8521 should work in either position in a C64.

(*) Does not apply to the UM6526, that's a TIA for the Atari 2600 :)

  Gerrit