Greetings
I have two Apple //+ systems, one functions fine and verifies the 3 floppy interface cards and 2 floppy drives are working.
The second //+ system fails to boot the floppy interface cards therefore no floppy drive access.
Any clues or suggestions on what to try or look for to troubleshoot?
Does the non-booting computer have the Applesoft prompt ] or the Integer Basic Prompt >
If Integer Basic try a PR#6 (assuming your disk controller is in slot 6) and see if it boots then. It would be rare, but a > prompt machine might not have the F8 Autostart ROM to know how to use the disk controller. If this is true, you have an Apple ][, not a ][Plus.
Did you try removing all cards except the disk controller?
Hi 8BitHeaven
With all cards removed it will boot to the AppleSoft prompt ]
If I install any of the 3 Disk II interface cards and power up, the Apple ][ text appears on the monitor then hangs without reaching the AppleSoft prompt ]
Ctrl-Reset or any keyboard input is ignored and only a power down works.
However, if I install the A2DVI card in ANY slot, that card will work but I get the same results on the LCD monitor as I would with the green crt when adding the Disk II interface card.
Upon further research I made an error.
I have an Apple ][ system that fails to boot the interface card.
and the working system is a ][ or ][+ CLONE
The original issue still exists but correctly identifying the computer system might change troubleshooting suggestions.
If it's booting to the Apple ][ screen, then it has at least the Autostart ROM. May be an original Apple II, but it probably has been converted to a ][+.
In any case, does the LED on the drive come on at all when you power on? The fact that ctrl-reset does not work could indicate a power supply issue. Without the disk card inserted, does ctrl-reset give you a new Applesoft prompt?
Yes, the floppy drive powers up and spins but does nothing but spin and Ctrl-reset does not work.
Yes, without the disk II card inserted the system boots straight to the AppleSoft prompt and Ctrl-Reset gives a new prompt each time.
I will pull the power supply and inspect
Also try putting the Disk Controller in each slot 1-7 to see if it works in another slot.
Tried that, no luck.
I probed the power supply, +5.18, +12.44, -4.73, -11.10
The negative outputs look low, maybe this is the issue?
That looks fine. Were these readings taken while the drive was running?
No, resting voltages at the output connector without plugging the psu onto the main board.
All three controllers show the same symptoms, and RESET stops working when the disk spins. If you've got a RAM card installed, these symptoms might indicate a faulty decoder in motherboard socket H2.
That is just a shot in the dark, but here's a simple test:
1. Turn on the computer without the Disk II controller. Do you get a BASIC prompt? Does CTRL+RESET work normally?
2. Let's just pretend there's a disk controller in slot 6. Pretend we want to turn disk drive on and off again by typing the command below and pressing RETURN at the Applesoft prompt:
PRINT PEEK(49385),PEEK(49384)3. It should print two random-ish numbers, but nothing else should happen because there's no disk controller. Did it print both numbers? Just one? Or none at all?
4. Press CTRL+RESET. Do you get a beep and a new Applesoft prompt?
If the computer printed only one number, and then RESET quit working, then your motherboard undoubtedly has a bad
74LS138in socketH2. causing multiple slots to be selected concurrently, so that disk IO interferes with the RAM card.2. Let's just pretend there's a disk controller in slot 6. Pretend we want to turn disk drive on and off again by typing the command below and pressing RETURN at the Applesoft prompt:
PRINT PEEK(49385),PEEK(49384)<-- tested 3 times3. It should print two random-ish numbers, but nothing else should happen because there's no disk controller. Did it print both numbers? Just one? Or none at all? Both numbers test1 0,160 test2 255,0 test3 160,0
4. Press CTRL+RESET. Do you get a beep and a new Applesoft prompt? Only when Disk II controllers are not installed.
Odd results;
Having removed the power supply, opening it, inspecting the components, closing it and mounting it back in the case.
After plugging it back onto the motherboard, EVERYTHING WORKS. Interface cards boot in each slot 1-7, floppy loads the DOS 3.3 floppy each time.
After powered on for about 10 minutes, changing the floppy disk and running PR#x (1-7) the drive spins up then hangs again.
I will re-cap the power supply before any more testing as it still has the RIFA cap in the psu.