Just wondering if anyone knows about any hardware differences (aside from the GAME ROM chips) on a Black Knight. Here's why:
I picked up a Black Knight to aid in writing System 7 test ROMs (http://pincoder.reversion.ca) and have found and fixed many issues with it using the (not yet released) test ROMs I wrote. The final problem with the machine is that it appears to possibly have some solenoid and lamp issues when running the Williams Version 4 roms.
The two most obvious errors are:
1) In attract mode: Most of the bulbs in the lamp matrix do not light in attract mode (The most obvious being the sword lights).
2) After starting a game: The lower left 3-blank drop target reset coil kicks in and STAYS ON.
After inspecting the wires and ensuring the proper wires are on the proper solenoids/lamps, and successfully running all of my system 7 test ROMS I can only conclude that the version 4 game ROMs are not compatible with this particular unit. It came with some dead version 3 game ROMs, and I have replaced them with working 2816 EEPROMs with version 4 copied on to them. So I'm now wondering if in fact the version 3 ROMs need to be used.
So my theory is that the version 4 ROMs are used in games with different wiring (ie playfield etc) than a version 3 game. I'm really doubting it, and I would like to eliminate this possibility. I've been looking for the Black Knight version 3 images on the net, but can only find V4. If you know where I could find some please send me a PM.
About the test ROMs:
They are in-game ROMs and test all of the RAM, CMOS, PIAs, CPU, chips on the CPU board and driver board as well as displays, solenoids, lamps, and switches. They even test the ROM sockets. All of these devices pass their tests. The solenoids and lamps can all be activated and deactivated individually using these tests, and all of the driver transistors are behaving as they should.
If anybody wants a pre-release version of these system 7 ROMs just PM me. They are almost complete. I still have to include the commas in the displays test.
Any help is greatly appreciated!