DWJ
Member
Early Sega/Gremlin (Dual VIC, Carnival, Pulsar, Invinco, Head-On, etc) boards
I'm currently figuring out the differences between the boards that have two rows of 2708s, but I think that my findings are going to be generalizable to the entire series of early Sega/Gremlin boards.
So let's open up with the the black-and-white games Head-On.
These boards appear to have been characterized by 8 2708 EPROMs. I don't have board revision numbers here (Outerworld, chime in here; I don't have any examples of this hardware to go on).
There's also Gremlin Board List, which partially covers the various generations of hardware.
Here's what I've been working with in my project:
Carnival:
- Sound board assy. 800-3057 (PCB 170-0199B)
U4 - AM8035-8PC
U5 - 2708 EPROM, "Carnival Sound A"
U6 - 28-pin socket, empty
U7 - AY-3-8910
- Main board:
Extended Rom Video Logic assy no. 800-0032
On the back, it's labeled PCB 0170-0156D
16 * 2708 EPROMs, 651A-666A
Z-80 CPU
U14: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0206)
U47/U48: both 8216
U49: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0633)
Pulsar:
- Has some other sound board I didn't document (yet). This board had no ROMs; just discrete components.
- The main board was identical to the Carnival set:
Extended Rom Video Logic assy no. 800-0032 (PCB 0170-0156D)
U14: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0206)
U47/U48: both 8216
U49: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0289)
Invinco, Head-On, others?
- I don't have a sound board for these.
- Main Board:
Dual Game VIC assy no. 800-0058 (PCB 0170-0174B) < (note "B")
16 * 2708 EPROMs, 271-286.
U47/U48: U47's a 74LS245 turned on its side relative to the rest of the board.
U49: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0287)
U57: Custom 40-pin DIP, 315-0042.
Another Carnival board, this time on the Dual Game VIC platform:
- I don't have a sound board.
- Main board:
Dual Game VIC assy no. 800-0058 (PCB 0170-0174D) < (note "D")
16 * 2708 EPROMs, 651-666
U47/U48: both 8216
U49: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0633)
U57: Custom 40-pin DIP 315-0042.
What's of interest here:
I have two "Dual Game VIC" boards marked "800-0058" on the front silkscreen, but on the back, the silkscreen reveals one to be one's a "B", and the other a "D". Both of these boards run the same software as an older "Extended Rom Video Logic" board marked 800-0032 (PCB 170-0156D)
The biggest change between 800-0032 and 800-0058 boards is the addition of a 40-pin DIP marked 315-0042.
The difference between the two revisions of the 800-0058 boards (PCB 0170-0174B and -0174D) is the replacement of two 8216 4-bit bidirectional bus driver/receivers with one 74LS245 8-bit bus driver/receiver. (Although the 8216s are on the "D" board, and replaced the LS245, which was on the "B" board...)
Back in the day, I had a multigame project that I never quite finished - a single 27128 can hold all 16 2708s, and there are pads for address lines adjacent to the CPU. Also of interest, I marked some pads for isolation, and did isolate at least one pad on one of these boards, and I think what I was trying to do (judging from my notes and the schematics) was test software compatibility by throwing four 2732s into U4, U8, U29, and U33 of the 16-chip dual VIC / extended ROM boards. Because Carnival and Pulsar - relatively new games compared to this vintage of hardware - are working on what appears to be an -0032 board, and because the 2708s I've pulled go all the way back to 139-146 (Space Attack?), I'm thinking that all these games will run on the same hardware.
OK, that's my core dump of Sega/Gremlin fun for now. Anyone else have a few of these boards laying around? And if so, what hardware differences can you find?
I'm currently figuring out the differences between the boards that have two rows of 2708s, but I think that my findings are going to be generalizable to the entire series of early Sega/Gremlin boards.
So let's open up with the the black-and-white games Head-On.
These boards appear to have been characterized by 8 2708 EPROMs. I don't have board revision numbers here (Outerworld, chime in here; I don't have any examples of this hardware to go on).
There's also Gremlin Board List, which partially covers the various generations of hardware.
Here's what I've been working with in my project:
Carnival:
- Sound board assy. 800-3057 (PCB 170-0199B)
U4 - AM8035-8PC
U5 - 2708 EPROM, "Carnival Sound A"
U6 - 28-pin socket, empty
U7 - AY-3-8910
- Main board:
Extended Rom Video Logic assy no. 800-0032
On the back, it's labeled PCB 0170-0156D
16 * 2708 EPROMs, 651A-666A
Z-80 CPU
U14: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0206)
U47/U48: both 8216
U49: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0633)
Pulsar:
- Has some other sound board I didn't document (yet). This board had no ROMs; just discrete components.
- The main board was identical to the Carnival set:
Extended Rom Video Logic assy no. 800-0032 (PCB 0170-0156D)
U14: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0206)
U47/U48: both 8216
U49: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0289)
Invinco, Head-On, others?
- I don't have a sound board for these.
- Main Board:
Dual Game VIC assy no. 800-0058 (PCB 0170-0174B) < (note "B")
16 * 2708 EPROMs, 271-286.
U47/U48: U47's a 74LS245 turned on its side relative to the rest of the board.
U49: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0287)
U57: Custom 40-pin DIP, 315-0042.
Another Carnival board, this time on the Dual Game VIC platform:
- I don't have a sound board.
- Main board:
Dual Game VIC assy no. 800-0058 (PCB 0170-0174D) < (note "D")
16 * 2708 EPROMs, 651-666
U47/U48: both 8216
U49: N82S123N / MMI 6331/ IM5610 (32x8 bipolar PROM) marked (316-0633)
U57: Custom 40-pin DIP 315-0042.
What's of interest here:
I have two "Dual Game VIC" boards marked "800-0058" on the front silkscreen, but on the back, the silkscreen reveals one to be one's a "B", and the other a "D". Both of these boards run the same software as an older "Extended Rom Video Logic" board marked 800-0032 (PCB 170-0156D)
The biggest change between 800-0032 and 800-0058 boards is the addition of a 40-pin DIP marked 315-0042.
The difference between the two revisions of the 800-0058 boards (PCB 0170-0174B and -0174D) is the replacement of two 8216 4-bit bidirectional bus driver/receivers with one 74LS245 8-bit bus driver/receiver. (Although the 8216s are on the "D" board, and replaced the LS245, which was on the "B" board...)
Back in the day, I had a multigame project that I never quite finished - a single 27128 can hold all 16 2708s, and there are pads for address lines adjacent to the CPU. Also of interest, I marked some pads for isolation, and did isolate at least one pad on one of these boards, and I think what I was trying to do (judging from my notes and the schematics) was test software compatibility by throwing four 2732s into U4, U8, U29, and U33 of the 16-chip dual VIC / extended ROM boards. Because Carnival and Pulsar - relatively new games compared to this vintage of hardware - are working on what appears to be an -0032 board, and because the 2708s I've pulled go all the way back to 139-146 (Space Attack?), I'm thinking that all these games will run on the same hardware.
OK, that's my core dump of Sega/Gremlin fun for now. Anyone else have a few of these boards laying around? And if so, what hardware differences can you find?
