On 23 Jan 2012 4:44am, John Robertson wrote:
David Shoemaker wrote:
According to mame there is rom covering the entire memory range from0-FFFF
ROM Regions: ...
So the ram / rom address space must be bank switched. Question is how to do that so I can get a good ram test with the fluke? I can do rom tests just fine so the board must default to the rom bank's.
Suggestions? As I recall the Defender Technical Service manual covered the bank switching in either the first (early board - 1 24 pin PROM) or second (2 PROM later boards) editions.
Yup, it's there...page 15 (Video Ram Control) of manual 16P-3001-301. Pretty sure they didn't change that at all (or very much?) for later boards.
The Memory map for Robotron etc is completely different to defender which is why the boards are not compatible in the slightest. From my notes that I use my 9010 with on Williams games, hope this helps! _Robotron Type Game Boards_ Video RAM 0000 -> 97FF Game RAM 9800 -> BFFF Colour RAM C000 -> C00F CMOS RAM CC00 -> CFFF ROM 0000 -> 8FFF (in 1000h blocks -- 2732's) ROM D000 -> FFFF (in 1000h blocks -- 2732's) ROM/RAM Toggle C900 (FF=RAM, 00=ROM in 0000 -> 8FFF) PIA (Widget) C804 -> C807 PIA (ROM) C80C -> C80F Special Chips CA00 -> CA07 Watchdog CBFF Video Counters CB00 (6 bits of video counter chain) Robotron type games need ROM 12 to do ROM test/rug (11 for Sinistar). _Defender Game Boards_ Video RAM 0000 -> 97FF Game RAM 9800 -> BFFF Colour RAM C000 -> C00F CMOS RAM C400 -> C4FF ROM (Banked) C000 -> CFFF (Bank Switched) ROM (Static) D000 -> FFFF (Not Bank Switched) ROM Bank Select D000 (0 = I/O, 1=Bank 1, 2=2, 3=3, 7=4) PIA (Widget) C804 -> C807 PIA (ROM) C80C -> C80F Watchdog C3FC Video Counters C800 (6 bits of video counter chain) Defender games need ROM 3 to rug and 3, 7, 8, 10 & 11 to do ROM test.