Pixels Past Bank Switch 8/16/32 Board - 27c256 EPROM - dumb question

[ruddy_canuck]

Hi - I'm testing the pixels past bank switching board and I wonder if I'm doing something dumb.

 

I have a bunch of 27c256 100ns eprom chips and was hoping to use them for 8k and 16k games. 

I've burned the PLD for F8 (8k) and tried a few different F8 games with no joy on a 2600 or the 2600+

(I'm confirming bank switching scheme in Stella and getting the F22V10 PLD binaries from here: https://grandideastudio.com/portfolio/gaming/pixels-past/)

 

I've also tried a couple of F6 (16k) games but still no joy. 

 

Am I being dumb - do I need to use the exact EPROM size? a 27C64 for F8 8k games and a 27c128 for 16k? (I don't have a F4 32k rom to test with.. anyone have one I can use?  )

 

 

Edited July 8 by ruddy_canuck

[glurk]

Try to double (or quad) your image and burn the entire EPROM.  This will account for any floating address lines.  This might do it...

[ruddy_canuck]

8 hours ago, glurk said:

Try to double (or quad) your image and burn the entire EPROM.  This will account for any floating address lines.  This might do it...

Of course!

 Thank you so much - I thought it was something simple that I was overlooking. 👍

 

If anyone else runs into this, be sure your burning software fills the rest of the EPROM. Like nature (and dogs), the 2600 abhors a vacuum.

 

Filling the rest of the EPROM with 0x00 (or 0x55, 0xAA etc - not null 0xFF) should also work. If all else fails, follow @glurk's idea and copy your image to fill the entire EPROM - that worked like a charm.

Cheers!