An Atari XEGS discussion

[mimo]

Thanks, that looks pretty cool but I am using an OE (not ingot) PSU 

[ArthurNor]

Evening. I appreciate this thread is a few years old now, but I'm struggling to find info online that clarifies exactly which Atari cartridges the Atari XE GS will play, for example do the Atari 2600 or Atrari 7800 cartridges fit and run on the XEGS? Thanks, Arthur

[+slx]

On 10/9/2023 at 9:29 PM, ArthurNor said:

Evening. I appreciate this thread is a few years old now, but I'm struggling to find info online that clarifies exactly which Atari cartridges the Atari XE GS will play, for example do the Atari 2600 or Atrari 7800 cartridges fit and run on the XEGS? Thanks, Arthur

Neither does. The 7800 can play 7800 and (most of) its own carts. The XEGS will play most Atari 8-bit cartridges (which are a bit smaller). Those it doesn't use some undocumented features / entry points for the operating system that changed from the older 400/800 computers to the XL/XE line. 

 

The 2600's and 7800's inner workings are quite different than the XEGS's. While the 2600 is generally simpler, its graphics chip can do a few mirroring tricks its descendant in the XEGS can''t match. AFAIK the 7800's MARIA chip (which is from different developers) uses a more sprite-based graphics concept which the XEGS would be unable to emulate on the fly.

[+slx]

Here's a list of XEGS cartridges and their memory requirements. Those listed with 64K are not going to work on a 400, those with 48 or less might work but whether they actually do depends on whether they try to use RAM bank switching that only the XL/XE are capable of. To find out if your 400 is 16K or more, you need a BASIC cart and try 

 

? FRE(0)

 

or if you don't have BASIC or any other programming language cart, disassemble it and inspect the memory card.