[SOLVED] Nemesis - Gradius, scroll repair

[Tailsnic Retroworks]

Hi. I have a Gradius board which has the scroll graphics movement stopped.

Everything is seen right, but for example, the background stars don't move, they are frozen.

The shinning efects of the stars work, so the animations are loaded, but the scroll graphic don't move as I say.

Where do I have to look after?

 

[ShootTheCore]

Start with the Scroll RAM - should be two 6116 parts at D22 and D25 on the video board.

 

[Tailsnic Retroworks]

Start with the Scroll RAM - should be two 6116 parts at D22 and D25 on the video board.

But says OK on the test. Alright, I'll test them

 

[Tailsnic Retroworks]

Ok @ShootTheCore. The 2 scroll rams are good, tested outside in TL866. Expanding the info about the SCROLL state, the level moves with you, objects, ships...but background stars are frozen

I'm starting to think those background stars are correct, and the "moving stars" are another layer not shown.

 

[Asure]

From some random Gradius youtube video, there should be several layers of stars moving around, i don't see a static non-moving layer at all.

 

[Tailsnic Retroworks]

From some random Gradius youtube video, there should be several layers of stars moving around, i don't see a static non-moving layer at all.

That's a good point. I'll keep invrstigating

 

[Tailsnic Retroworks]

In Gradius, 22D is the ram in charge of scroll graphics and 25D of object graphics. I have tested the error screen quitting each one.

Said this:

Desoldered and tested 23A, 23B, 23C directly involved with 22D inputs, and indirectly 22A, 22B and 22C whose logics are used in 23A-B-C inputs. Of all of the LS157, one was bad in triplets 23 line.