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Replacing 8332 Masked ROMs on
Vectorbeam & Cinematronics Hardware

8332 Masked ROMs replaced with 2532 EPROMs


Some older Vectorbesm and Cinematronics CPU boards were wired for 8332 masked ROMs rather than 2716 EPROMs. When these masked ROMs need to be replaced, the board will not use regular EPROMs without some addtional work.


There are two options for replacing masked ROMs: use two modified 2532 EPROMs installed into the CPU, or use two standard 2732 EPROMs installed into the Cinematronics EPROM PCB. For either, new binaries combining the ROMs in the P & R sockets and the T & U sockets must be used. See below to download ready-made copies of these images.

A 2004 post by Matt Rossiter details the solution using 2532 EPROMs. The combined images are burnt to two 2532 EPROMs and pin 21 is bent outward on each. Then, jumper wires are soldered between pin 21 and 24. This causes pin 21 to be held active high rather than active low. The ROMs are then ready to be installed in P7 & T7 on the CPU board and power applied.

Using the Cinematronics EPROM PCB, the images are burnt onto two 2732 EPROMs. These EPROMs are installed in the daugherboard in sockets P7 and T7. After properly setting the jumpers on the board for this application, the board is ready to be powered up.

Downloads to Replace Masked ROMs

Below are download links to combined ROMs, that (with the exception of Warrior) I have tested and confirmed would run on my Tailgunner PCB. They are ready for burning to either 2532 or 2732 EPROMs depending on your choice of installation.

Space War(s)
Speed Freak
Warrior (not yet tested on masked ROM hardware with JMI installed)