Sinistar General Team Revisions Tricks Duramold My Project

Current Project

I am going to try creating a multiple revision version of Sinistar.  I hope to collect all of the revisions, and burn them to one or several EPROMS.  Once that is done, I am going to try to design a daughterboard using the wonderful conversion documents by Doug Jefferys and Sean Riddle.  Wish me luck! 

If you have any information about the whereabouts of the missing ROMS, or other information that can guide me in my quest, please let me know.

If I get the thing working, I will post my notes to this page. 

Marquee repair - 3M Auto Body Rubbing Compound Fine Cut does a phenomenal job getting rid of the scratches in the marquee.   I would imagine that a polishing compound could be used after the rubbing compound to further clean up the marquee.

I just picked up an eprom burner from I got the PACKAGE EPROMER5-003. It supports the 2732 chips, but can not read or burn the 2532 found on the sound and speech cards. It can program a 27C040 and 27C080.


Project Goal: Modify a existing Sinistar to run all the revisions of Sinistar.

Starting point Williams_conversion document by Doug Jefferys

May also want to add nsayer hack for CMOS

Tools needed:

Supplies needed:  Can be purchased from Jameco or Digi-key

1 - Working Sinistar machine.
  ROM images for other revisions of Sinistar
1 - 27C040 EPROM 450ns or faster (Digikey part# AM27C040-120JC-ND) $10.58

* If it says OTP, that is One-Time-Programmable, so you can't erase the EPROM once it has been programmed. We want a CDIP, PDIP, or SOIC style EPROM. We do not want a TSOP or a PLCC. The TSOP has the legs out the side and the PLCC has them curled underneath.

I was informed that the C in 27C040 stands for CMOS. I was told that there is no such thing as a 27040, because dropping the C refers to the older NMOS or DMOS technology. The older technology was never used to make a chip as large as the 27C040.

1 - 7400 quad NAND IC (for ROM address decoding).
1 - 32-pin socket (for CPU ROM).

1 - 28-pin socket (for sound ROM).

1 - 6264 SRAM or Dallas DS1225Y non-volatile SRAM

1 - 7404 hex inverter chip
1 - 74133 single 13-input NAND chip (no, that's not a typo :-)
1 - 16-pin socket
1 - 14-pin socket
1 - 28-pin socket
3 - 24-pin sockets
1 - 28-pin ZIF (Zero-Insertion Force) socket
1 - 24-pin ZIF (Zero-Insertion Force) socket
1 - 4-pin .100" male strip header
5 - 12-pin .100" male strip headers
1 - 12-pin .100" female MTA plug
1 - 4-pin .100" female MTA plug
1 - chunk of blank breadboard, .100" spacing, about 2.5 inches square

some kind of game select switch- a 4 pin DIP switch or an 8 (or more) position rotary switch (mine has 12 positions) or my software ROM switcher circuit and code
        ...sockets, plugs,

Other parts to get to fix my machine:

Light bulbs (type 44? or 47?)
Light bulb in coin door.
Ribbon cable that is bad. - Bought several from Bob Roberts. It appears that these cables get bad over time. Replacing it got rid of the RAM errors.
PCB Connector DigiKey pg. 17/587 (40 contact full row version 2.2 inch, 55.88 mm CPC40T-ND $2.60)

Any other part that is bad, or that needs replacing.
Find loose wire

  1. Create a ROM file that is correctly padded using rom_create script.
  2. Use the WILCHKSM program from Sean Riddle to verify that the 512 K ROM images are built correctly.

1.3) Create the program ROMs, using 27C040s.  Put all verions of the game onto one ROM.

512 KB EPROM - 27512 is 64K x 8
4 MB EPROM - 27C040 is 512K x 8 - This can hold 8 versions of Sinistar. Since there are only five know revisions (only three of which have been located), this is more than enough. There is room to add other Williams games like Robotron, Joust, etc.

Digikey AT27C080-90PC-ND is $10.58 and is a 27C080 (8 MB) 4.5 V to 5.5 V

65,536 * 8 = 524,288 (512K)

Use rom_create script

1.4) I decided to restrap my sound board to use 2732 EPROMs, rather than 2532s.
Since the 27256 that we are adding is more similar to the 2732, this simplifies
the adapter that we have to build.

Join the sound files together in the same order that you placed the game files.
Use 4,096 hex 0xFFs to leave blank spaces, and pad the file with hex 0xFFs
until it is 32,768 bytes in size (32K).

2.1) Burn the 27040 multigame EPROM.  If your EPROM burner doesn't handle 27040
EPROMs but can burn 27512 EPROMs, you can easily build an adapter that will let
you burn a 27040 one game at a time. ***27040/27512 hack ***

2.2) Burn the 27256 multisound EPROM.

3) Instead of looking at the 12 signals that select one of the 12 EPROMs, I look at the four signals that indicate that the EPROMs AREN'T being accessed.  This eliminates soldering nine wires to the ROM board, and also gets rid of the 74133 IC.  Simply checking the four non-EPROM signals coming from the 74154 is not enough to select our multi-game EPROM, though, because the '154 also has two strobes that must be low for those four signals to be meaningful.  Luckily, five of the six signals we need to check meet at one gate- a four-input NOR gate with strobe (IC 2E, a 7425).  We can use the output of this gate, along with one more signal and the strobe input to this gate, to generate the output enable signal (*OE) for our multigame EPROM.  All we need are the 4 NAND gates from a 74LS00 IC (a very common chip, even available at Radio Shack).  And all of the signals that feed into the 74LS00 except one are
available at the CPU board connector, so only one wire must be soldered directly to a chip.

4.2) Restrap the sound board.  *** restrap sound board hack ***

Q: What is the 74154?
A: 1-of-16 inverting decoder/demultiplexer

Q: What is a !CS signal?
A: Logical Not Chip Select signal. It means that the Chip Select is NOT selected.

Q: What is a strip header (5.2)?

Q: 5.9?  What is it asking?  Should it be cram the 28-pin ZIP socket....