Help needed with 1200XL, U1MB & CARTRIDGES

[+videofx]

CARTRIDGES TRIED:

 

1. Ultimate

2. Basic XL

3. Miner 2049'er

4. Action

5. Mac 65

6. Bug Hunt

 

 

1. With PBI BIOS disabled and SDX enabled with XL BIOS

 

At D1: prompt, type CAR you get garbage for a second the back to D1: prompt

 

2. With PBI BIOS disabled

 

Goes directly into Self-TEST

 

No matter what settings I choose cant get cartridges to work

 

Any help would be greatly appreciated!

 

Thanks!

[flashjazzcat]

Sounds like an RD4/5 issue since there should be no problem with this at all. Check continuity of connections from the MMU socket to the U1MB header, and from the cartridge connector to the MMU.

 

Schematic here:

 

https://jsobola.atari8.info/dereatari/atarisch/1200xl.zip