MASTER SYSTEM 2 WITH GARBLED GRAPHICS

I got this SMS2 and it gives me garbled graphics, audio is good, sega logo is good and also the r-type title screen, then sprites and background become a mess. Same thing with the alex kidd game built in memory.

could be a Z80 problem?

thanks

 

Start by doing a good visual inspection of the board inside.
You can also take pictures and ask for support on the forum.

This could be a bad chip as you say but this can also be a bad trace or cold solder joint.

 

Try reflowing the solder on the VDP chip. My SMS1 booted up for 2 seconds and then the video cut out along with the sound, recapped it and it didnt work, so I reflowed the VDP and voila. Got it for 10 bucks from a guy who thought it was done.

 

thanks everyone, I tried resolder the vdp points but nothing changed, under the pcb there is a scratch on the traces comin out the vdp, wonder if this is the problem....I should buy a multimeter (and learn how to use it)

 

That scratch does not look like it is deep enough to sever a trace but hard to tell from the picture.
You can try cleaning the scratch with a q-tip + alcohol and looking at it with a magnifying glass.
But ultimately, the multimeter does not lie.