The A8 personality chips....were there different revisions/versions

[carmel_andrews]

Following on from the thread about A8 machines sounding different

 

 

It begged the question, did Atari get around to doing different revisions/version of the personality chips (i.e. pokey antic c/gtia)

 

Or where the 4/800 versions the same as the xl/xe versions and visa versa

 

If different revisions/versions were made, where there noticable differences in audio or video/gfx output as well as any other differences

[Rybags]

The chipset ie Antic, GTIA etc aren't the personality chips.

 

References to personality boards are usually referring to the OS module in the 800 which only contains the OS, not any custom chips.

 

C/GTIA is almost self-explanatory. Since there's buggy (Chinese?) versions of GTIA it's possible there might have been some revision change although I suspect it was more a case of bad fabrication which caused the GTIA modes to not work properly.

 

Antic, there is at least 2 revsions - the later E type produces an extra row in the refresh generation.

 

Of course all this is ignoring Pal/NTSC, so you can essentially say there's Pal and NTSC versions of Antic and GTIA. Pokey is the same on both, so the audio is slightly different pitch due to the clocking speed difference.

 

PIA - doesn't count IMO, not really a custom chip, it's an off-the-shelf part.

 

Then you have others such as the various MMU and EMMU types and Freddie. AFAIK there's just the single Freddie version in production machines although it's not a chip you directly access, it's essentially a custom part which was designed to reduce the overall chip count and make the machine more stable.

[Tempest]

Antic, there is at least 2 revsions - the later E type produces an extra row in the refresh generation.

Interesting, never heard of that before. What are the consequences of the extra row?

[Bryan]

Interesting, never heard of that before. What are the consequences of the extra row?

Nothing visible, it just allows for higher density RAM chips.

[ClausB]

Really it's 128 extra rows. The old ANTIC has 7-bit refresh and the new has 8.

[Bryan]

It's more refreshing. Like Irish Spring.