Pengo High-Score Saver

Overview

Pengo !!  Time to add some battery backed RAM to this classic !  Already using 2k x 8 SRAM on the original game board makes life a lot easier, simply replace the ROMs and add in an SRAM.

There's a couple of issues, one being the SRAM might not fit into the boards RAM socket very well, in which case a wirewrap socket is required, and the second is a minor pain.....

It appears that the first release/s of Pengo used a Custom CPU, a z80 with some encryption hardware, but the later versions did not and had unencrypted ROMs and a regular z80A CPU. The new game images are designed only for the unencrypted version of the board.

If your board is the first variety with the 'custom controller' at location IC2 you will need to replace it with a plain z80A, the 'A' is important and a Z80B or Z80C will also work,  or a D780 which is an NEC z80 equivalent.

Patch Source Code

Source codes !! Yes, I'm sharing the source for this one ;-)   Here are the the source codes to the hack plus note on what was changed in the original game ROMs.

It's designed for use with the TASM cross assembler for DOS.

Pengo High-Score Save Sources and ROM Patch Details.

 

Game Updates

Requirements

Dallas 1220  battery backed SRAM & 24pin wirewrap socket*
Eight 2732 ROMs with new program images
Z80A CPU**

*if the SRAM does not fit into the socket for IC19 a wirewrap socket will be required.

**with the later Pengo boards the 'custom controller' appears to have been replaced with a regular Z80a CPU, if your board does not have the z80 you WILL need to replace it for the updates to work.


Board Overview

The picture below shows the areas of the board that'll be of interest.

One of the original 2k x 8 SRAMs on the board will need to be replaced with a Dallas SRAM, outlined in red,
the z80a is outline in pink and the ROMs that will need to be replaced in Yellow.

Board Overview     

IC2 (z80a)  and IC19 ( battery backed RAM ) closeup

Close up view,  Z80 CPU at top in location IC2

Battery backed SRAM at location IC19



RAM & Sockets

The sockets on the pengo boards I tested with have very high-edges and this makes the RAM not fit very snugly. To get around this problem I used a 24pin wire wrap socket.The wirewrap socket has long pins and fits very tightly into the socket. 

RAM in 24pin Wirewrap socket SRAM inplace on board
SRAM in 24pin Wirewrap socket

Socketed SRAM inplace

*NOTE: The new battery backed SRAM replaces the standard 2k x 8 SRAM in socket 


ROM Placement

The new program EPROM filenames match the following board locations, all EPROMs are 2732 ( 4k x 8 ).

Download the high-score save Game Program images

Pengo High Score Save Program Images

 

Pengo HSS 

Go back to Save Our High Scores