ivan stewart off road/track pack issue with screen/board

[DogP]

That seems to be a very common problem w/ these PCBs... you should definitely do a search. Unfortunately, I think it might be specific to Track Pak, and I seem to remember someone saying they deconverted from Track Pak to regular and the problem went away. I don't remember if they posted that they verified the ROMs... if that was the case, it would mean that the security chip caused it, or some hardware that Track Pak uses, but the regular game doesn't.

I actually seem to remember having this problem on one of my boards... I don't think I ever fixed it (it's probably in a box somewhere).

DogP

 

[tron guy]

is the z80 on the top board just a z80 or is it a z80B z80C etc? if it's just a z80 or a z80A then your z80A should be fine. If it's a z80B or C or whatever it probably won't work.

They are Z80Bs on that board........

The z80 has written on it the following:

U67
Z8040006PSC
Z80 CPU
8922 JT

Is my Z80A compatible?

 

[p1899m]

based on what it says on the z80 it may be. Or maybe someone put the wrong z80 in there. At any rate I don't think it will hurt anything to try one of your z80's in there. I think the z80B and C etc are just faster speeds so if anything it just wont work or might lock up or something but still may give you a glimpse of hope if it shows signs of correcting the issue.

 

[tron guy]

ok I put my z80A in there and it works exactly the same.

same issues in test mode with the background screen, etc.

all the ram and rom tests come out good, it's just that background screen in test mode. Which makes the game unplayable.

 

[tron guy]

does anyone know how I would go about getting the original roms to put back in there and get rid of the track pack? And does this typically fix the issue with the track pack boards?

 

[Zork2]

Steph from Hobbyroms.com could probably burn you a set. Not sure how much that would cost though, I think there are quite a few chips in that set? One problem being that security chip. I think the regular version runs a different security chip that is not compatible with the trac pac......
Ask Steph, he should have the answers......

 

[DogP]

Steph from Hobbyroms.com could probably burn you a set. Not sure how much that would cost though, I think there are quite a few chips in that set? One problem being that security chip. I think the regular version runs a different security chip that is not compatible with the trac pac......
Ask Steph, he should have the answers......

Actually, I'm pretty sure the regular version doesn't have a security chip at all... that was added with the Track Pak. But yes, there are a LOT of ROMs (I think 20+ EPROMs).

DogP

 

[tron guy]

Well I have been doing a lot of reading up about peoples issue with these games.


I noticed in one thread that arcaded (I think was his name) mentioned that his bottom board wasn't at +5 unless his power supply was pumped up to over +6

I have my power supply at 5.23 and I am getting 5.23 on the legs of the rams chips and other test points on the top board. It didn't occur to me to try to test the bottom board because it seems very hard to do while hte board is in the game.

Any chance my "shifted screen" is just a power issue?

Where is a test point for the bottom board?

 

[bheineck]

Does anyone know how to tell from the game play and screens if the board inside the game is a Track Pak version or does the board have to be pulled? I have a working game and I am wondering, because the marquee says Track Pak, but I would like to verify.

 

[Ghostnuke]

The title screen will say Track Pak.

 

[bheineck]

Hmmmmm...... I don't recall if it did or didn't. Haven't played in a while. I'll have to check. thanks.

The title screen will say Track Pak.

 

[tron guy]

when you coin up you will get to choose between a dune buggy or off road truck.

Original version is the truck only ( I believe)

 

[Adamdiz]

Correct the original is only a truck.

when you coin up you will get to choose between a dune buggy or off road truck.

Original version is the truck only ( I believe)

 

[bheineck]

Suck.... no Track Pak! Hopefully the possibly working extra board set I bought works, because it is a Track Pak board I believe.