I was chatting to a fellow collector last week about a faulty Phoenix board he has, and we got talking about a test ROM for the board.
I had a bit of time this weekend so adapted the Moon Cresta/Scramble/Super Cobra test ROMs that I put together a while ago, and the result is a test ROM for Phoenix. As it happens exactly the same test ROM works for Pleiads as they run on pretty much the same hardware. It's been tested on an original Amstar and a bootleg Phoenix board (although all Phoenix boards I've ever seen are identical), and a Centuri Pleiads, so should work on all variants.
The one drawback is that it relies on being able to display the results of the tests on screen, so if your board is completely dead it won't really help you...
The test ROM tests both banks of the 2 x 1K areas of RAM (4000-43FF & 4800-4BFF), and also displays the status of inputs and DIP switches. An explanation of the tests follows, and photos of the tests are attached, some from Mame and some from a real Phoenix board
Pic 1 - First powered up, and during testing - it writes a number of values to each RAM location and reads back to ensure the correct value has been stored. The screen will show a constant changing pattern.
Pic 2 - RAM test failure and it displays the bank and RAM area at the top of the screen. If it fails then it stops all further tests, so this may not be the only fault. The failure below indicates RAM area 4000-43FF, bank 0 (RAM 0 Bank 0). This is (on Phoenix) IC41/IC43. The other failures (again on Phoenix board) indicate:-
Bank 0 RAM 1 - IC42/IC44
Bank 1 RAM 0 - IC25/IC27
Bank 1 RAM 1 - IC26/IC28
On Pleiads:
Bank 0 RAM 0 - IC40/IC42
Bank 0 RAM 1 - IC41/IC43
Bank 1 RAM 0 - IC22/IC24
Bank 1 RAM 1 - IC23/IC25
Pic 3 - Passed RAM tests, and here it tests DIPs and inputs
DIP switches 0-6 can be read and displayed. DIP switch 7 (cocktail mode) can't be read by the game, instead bit 7 displayed on the picture is the VBlank signal (so meaningless really as far as tests are concerned). In these tests, 0=on
The player inputs are BLRF-21C, which are Barrier, Left, Right, Fire, Not used, P2 start, P1 start, Coin - 0=pressed/selected
You need to burn the test code to a 2716 EPROM, and replace IC45 (Phoenix) or IC47 (Pleiads). 4th pic shows it installed on a Centuri Pleiads board.
Test ROM code is attached.
I had a bit of time this weekend so adapted the Moon Cresta/Scramble/Super Cobra test ROMs that I put together a while ago, and the result is a test ROM for Phoenix. As it happens exactly the same test ROM works for Pleiads as they run on pretty much the same hardware. It's been tested on an original Amstar and a bootleg Phoenix board (although all Phoenix boards I've ever seen are identical), and a Centuri Pleiads, so should work on all variants.
The one drawback is that it relies on being able to display the results of the tests on screen, so if your board is completely dead it won't really help you...
The test ROM tests both banks of the 2 x 1K areas of RAM (4000-43FF & 4800-4BFF), and also displays the status of inputs and DIP switches. An explanation of the tests follows, and photos of the tests are attached, some from Mame and some from a real Phoenix board
Pic 1 - First powered up, and during testing - it writes a number of values to each RAM location and reads back to ensure the correct value has been stored. The screen will show a constant changing pattern.
Pic 2 - RAM test failure and it displays the bank and RAM area at the top of the screen. If it fails then it stops all further tests, so this may not be the only fault. The failure below indicates RAM area 4000-43FF, bank 0 (RAM 0 Bank 0). This is (on Phoenix) IC41/IC43. The other failures (again on Phoenix board) indicate:-
Bank 0 RAM 1 - IC42/IC44
Bank 1 RAM 0 - IC25/IC27
Bank 1 RAM 1 - IC26/IC28
On Pleiads:
Bank 0 RAM 0 - IC40/IC42
Bank 0 RAM 1 - IC41/IC43
Bank 1 RAM 0 - IC22/IC24
Bank 1 RAM 1 - IC23/IC25
Pic 3 - Passed RAM tests, and here it tests DIPs and inputs
DIP switches 0-6 can be read and displayed. DIP switch 7 (cocktail mode) can't be read by the game, instead bit 7 displayed on the picture is the VBlank signal (so meaningless really as far as tests are concerned). In these tests, 0=on
The player inputs are BLRF-21C, which are Barrier, Left, Right, Fire, Not used, P2 start, P1 start, Coin - 0=pressed/selected
You need to burn the test code to a 2716 EPROM, and replace IC45 (Phoenix) or IC47 (Pleiads). 4th pic shows it installed on a Centuri Pleiads board.
Test ROM code is attached.
