Rastan saga bad graphics.

[Lurch666]

I now have the rastan PCB that Griffox83 asked me to repair.
Repair wanted thread:https://www.ukvac.com/forum/threads/pcb-repair.85201/

Since I had repaired my own faulty PCB with similar faults I started with piggybacking some ram and found two bad which I replaced:


And now a lot of the lines are gone:



Sprites still a mess and missing bits. Will look at the 157s which were mostly bad on my PCB as it could be the same with this one.

One thing that puzzles me is the replacement for one of the graphic mask roms:


It's been replaced by a 27512.
On mine the when I replaced a rom I had to use a modified 27c1000 so I'm thinking I will need to change this.
Will look once I got the rest of the sprites sorted.

 

[griffo83x]

wow great progress , yes the mask rom was replaced in the past , i was told that was the issue , quite a few years ago so cant really remember to be honest

 

[Lurch666]

I should really learn from my mistakes.
When I was fixing mine I used a bad 2018 ram because I didn't have a method of testing them.
Now with my working PCB I can use the test mode to check the 2018 rams and found one I used in this faulty PCB was bad. Grabbed another from my donor PCBs and now the game is working 100%

 

[TheDaddy]

Cracking repair mate !

Dave.

 

[Retroman839]

Well done

 

[Del Griffith]

Nice job.

 

[griffo83x]

Brilliant be great to play this again