Faulty Ram?

4 posts / 0 new
Last post
Offline
Last seen: 11 months 1 week ago
Joined: Dec 8 2020 - 11:26
Posts: 6
Faulty Ram?

hi guys,

 

im messing around with a broken iic (us version) which i got here in germany...

It wont post / shows marbled graphics.  It tries to read from my floppy emu but ends with errors...

 

i managed to check system with rom4x

(most of the time the machine gets stuck while testing maybe in 1/100 i got different Ram Errors...)

 

PICTURES:

 

 

https://bilderupload.org/bild/a01a45189-96120971-1021911182579946

https://bilderupload.org/bild/55c545181-96428022-1021911182615947

https://bilderupload.org/bild/e1d545163-130223672-102207176541441

 

is this because of faulty ram? i am able to swap these but im not an pro with osci and so on... is there a chance to fix this or might there be more involved like broken IWM ?

Rgds Dario

 

 

Tom Owad's picture
Offline
Last seen: 2 days 1 hour ago
Joined: Dec 16 2003 - 15:14
Posts: 3150
Does this happen with both

Does this happen with both the original ROM and with the rom4x? I assume you're not able to get into BASIC?

The screen that says "RAM 00001011" - is that the result of the RAM test telling you which chip is bad?

 

To share photos, please use the 'Media browser' link in the editor toolbar, rather than linking externally. It helps these discussions to remain useful long-term.

Offline
Last seen: 11 months 1 week ago
Joined: Dec 8 2020 - 11:26
Posts: 6
Yah - this is the result, but

Yah - this is the result, but results are different every time (most of the time no result at all)

 

i probed the the ram with an osci today and all databits and refresh look the same.. so i  assume its not the ram

Offline
Last seen: 6 months 6 days ago
Joined: Mar 31 2020 - 19:55
Posts: 848
twitch wrote:Yah - this is
twitch wrote:

Yah - this is the result, but results are different every time (most of the time no result at all)

 

i probed the the ram with an osci today and all databits and refresh look the same.. so i  assume its not the ram

If you can boot to BASIC, load the Monitor with CALL -151 

 

Flood the ram with different values, one bank at a time, then read it back. See if you can find a specific bank that is mirrored or stuck. 

Log in or register to post comments