Got a Black Widow board that has no vector output, and it makes a repeating sound like an old 45 record skipping. Self test does the same thing.
Probing pin 40 of the CPU reveals the board is in constant reset.
Hooked up the Fluke and pressed the key to do a Bus Test, which sees if the CPU can control the address bus lines and the data bus lines. The Fluke says "Active Force Line - Loop?" which means certain pins are forcing the CPU (or pod in this case) into a certain state. Pressing the More key shows "STS BTS 0001 1000" and the legend on the pod itself shows that for the 6502 those Status bits are the IRQ and the RESET lines. Looping won't help; we must tell the Fluke to ignore those Force lines. Do so by pressing the Setup key and then More until you get "Set-Trap Active Force Line? Yes" and then press the No key to change it.
You can then immediately press the Bus test key again and it should run.
On this board we get "Data bit 3 tied High - Loop?" We don't want to loop but we want to know if there are any other problems, so press No. We also get "Data bit 4 tied high" and then a whole series of bit pairs tied (together): 0 and 3, 0 and 4, 1 and 3, 1 and 4, 1 and 2, 2 and 4, 2 and 3, 3 and 5, 3 and 4, and 4 and 5. The last error is "Data bits 6 tied - Loop?" So clearly there are troubles on the data bus.
Probing pin 40 of the CPU reveals the board is in constant reset.
Hooked up the Fluke and pressed the key to do a Bus Test, which sees if the CPU can control the address bus lines and the data bus lines. The Fluke says "Active Force Line - Loop?" which means certain pins are forcing the CPU (or pod in this case) into a certain state. Pressing the More key shows "STS BTS 0001 1000" and the legend on the pod itself shows that for the 6502 those Status bits are the IRQ and the RESET lines. Looping won't help; we must tell the Fluke to ignore those Force lines. Do so by pressing the Setup key and then More until you get "Set-Trap Active Force Line? Yes" and then press the No key to change it.
You can then immediately press the Bus test key again and it should run.
On this board we get "Data bit 3 tied High - Loop?" We don't want to loop but we want to know if there are any other problems, so press No. We also get "Data bit 4 tied high" and then a whole series of bit pairs tied (together): 0 and 3, 0 and 4, 1 and 3, 1 and 4, 1 and 2, 2 and 4, 2 and 3, 3 and 5, 3 and 4, and 4 and 5. The last error is "Data bits 6 tied - Loop?" So clearly there are troubles on the data bus.
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