Outrun sprite issues

[sosfx]

Hi Guys,

Hoping someone can let me know what's going on with my outrun.

Has been on for most of the day playing fine and then this

mem test comes back ok?

plays fine just can't see any cars or game sprites as they are glitching all over the place

So please do let me know what you all think? bad Roms?

thanks in advance for any help

sosfx

 

[beckscc2010]

For me it was a bad ram (mem test was ok also)
Maybe you can post a video

 

[TheDaddy]

Cant see your pictures very well as they are too small !!

Turn it off and let the board cool down for an hour or so , When its powered on after the hour or so does it do the same ??

From what I can see it could be voltage issue, Make sure that there is a steady 5v going to the Board and chips. Past that it will be a Ram, Rom or TTL issue.

Hope this helps.

Dave.

 

[tin]

Mine had same issues and was just a couple of cheap chips - that I presume without much investigation - just mixed the graphics.

 

[big10p]

To see bigger pics: right-click on them and select 'Open image in new tab'. That's in Chrome. Dunno about other browsers.
big10p2019-02-09 21:25:06

 

[tin]

Firefox, right click > view image

and bin off chrome, my god.

https://www.theverge.com/2018/1/4/16805216/google-chrome-only-sites-internet-explorer-6-web-standards

 

[sosfx]

Sorry for the small pictures,
please see the video below

thanks

sosfx

 

[Equites]

What's you're soldering like?

 

[sosfx]

its ok, not gonna win any awards but it should work after and mostly does

why, do you know what's up with it?
sosfx2019-02-09 23:52:32

 

[dave11674]

Following
As my outrun is in need of repair too

Thanks

 

[ar2r]

I had something similar although not that severe. the sprites would flicker, look like garbage etc.

resolved by replacing several rams on the bottom board (from manual video board 3/7)

in my case those were HM65256 ...

 

[dave11674]

Thanks ar2r
Did you find direct replacements
Or did you have to use alternates ?
If alternates which suffice in place as im just about to order
Repair parts
And want to get all ram chips in one swoop if poss

Thanks

 

[ar2r]

searched long and hard for those and could not find replacement for slim ones (300) only for 600.

if you want to replace them all it should be possible to swap them all from 300 to 600

here are the links

300:

https://uk.utsource.net/pro/HM65256BLSP-10.html

600:

https://www.mouser.co.uk/ProductDetail/Alliance-Memory/AS6C62256A-70PCN