First post, by DonutKing
- Rank
- Oldbie
as many of you already know, the SB 2.0 requires 3 chips to enable Game Blaster/CMS compatibility. Two Phillips SAA1099 which are pretty easy to find, and one PAL chip that is Creative proprietary.
Chuck(G) over at vintage computer has managed to dump the contents of the missing chip.
http://www.vcfed.org/forum/entry.php?328-Clon … HAL-PAL-Part-11
CHIP SB20 16V8 […]
CHIP SB20 16V8
pin1=1 pin2=2 pin3=3 pin4=4 pin5=5 pin6=6 pin7=7 pin8=8 pin9=9 gnd=10
pin11=11 pin12=12 pin13=13 pin14=14 pin15=15 pin16=16 pin17=17
pin18=18 pin19=19 vcc=20EQUATIONS
; pin12 = nc
; note that pin 7 8 and 9 are tied to gnd on the PAL socketpin13.trst = /pin4
pin13 = pin7 ; IO CH RDY/ tristated
/pin14 = pin11*pin3*/pin2 ; CS/ for YM3812
/pin15 = /pin5*/pin3*/pin2 ; CS/ for first SAA1099P
/pin16 = /pin5*/pin3*/pin1 ; CS/ for second SAA1099P
/pin17 = /pin11 + /pin6 ; U14, 74LS74, PS2
/pin18 = /pin5*/pin3*/pin1 + /pin5*/pin3*/pin2 ; U14, D2
/pin19 = pin5 ; U14, CLK2
If you run this through EQN2JED then burn a GAL16v8 in an appropriate programmer you should be able to get the CMS upgrade working.