Re: 1551 Repair - 28 pin 6523 Wanted

From: Gerrit Heitsch <>
Date: Sun, 09 Mar 2014 10:10:28 +0100
Message-ID: <>
On 03/09/2014 10:01 AM, smf wrote:
>> If set to input in the DDR they should read as '1'
> Only if there is a pull up resistor on the undefined bits, which there
> may or may not be.

If it's the normal 6525 die (and I doubt Commodore made a new die just 
for that, much easier just use a different package), then there should be.

Should be easy enough to check by someone with a working 6523T.

> (*) I'm guilty of that though, so I admire the intention to get it
> right. I guess there is a potential that someone wrote custom code for
> accessing the 1551 as well, so just looking at the rom isn't necessarily
> enough.

As far as I know, there are some speeders for the 1551.


       Message was sent through the cbm-hackers mailing list
Received on 2014-03-09 10:00:37

Archive generated by hypermail 2.2.0.