Commodore 8296 - Wierd Boot message

[HammysHangout]

So, i been live streaming a commodore 8296 repair ( vods up on my youtube;https://www.youtube.com/user/ki4swy )

However, i am at the stage of getting this on bootup:



I don't have a keyboard, so thinking it maybe a result of a bad 6520?

So far had to to replace 5 logic chips, and both PLA(s) and the 6545 and Character Rom to get this far.

 

[daver2]

It may be I/O based, alternatively, it may be faulty RAM.

I have never tried this (yet!) but do you want to try my PETTESTER ROM in place of the EDIT ROM at $E000? This was designed for a “bog standard” PET, but it may work on your 8296?

It relies on the restart vector and the first few bytes of instructions in the kernal ROM at $F000, and then the correct entry point into the EDIT ROM from the kernal ROM. Happy to make any changes required to support the 8296...

EDIT: Just checked an upload of the firmware from an 8296 and it should work with my PETTESTER. The hardware initialisation entry point into the EDIT ROM is $E000 (as per BASIC 4).

Dave

 

[HammysHangout]

So, after doing some testing, turned out the Kernal/Basic rom as not burned right.. I ended up putting the stock one back in and it booted just fine.. returning back out to customer , will get final post op video on youtube tommorrow.

 

[daver2]

Interesting. Where did you get the image from out of interest?

I noticed that one of the images on Bo’s website appears to have an extra 16 bytes in it over and above what I would have expected.

Dave

 

[HammysHangout]

I just saw this post, i don't remember i have since returned the board to the owner as i was finished working on it.