Hugo Holden
Veteran Member
Recently I acquired a Commodore 1541 drive, the AH5050 pcb and the AH5050 ROM (which goes in the AIM65's assembler socket)
The drive itself looked almost NOS, has had little use, but it could still be defective.
When I attempt the use it, by typing N which sends the processor to D000h (where the ROM is), the error DRIVE NOT READY 00 00 is reported on the display.
But prior to this the drive starts up, makes a number of noises and when it stops, the red LED on the drive body blinks rapidly. I have a new un-formatted disk in the drive. But because I cannot get past the initial error I cannot format it.
So it appears the drive is responding initially, but in some way not working. (I have the disk inserted correctly and the drive handle closed)
I don't have any other computer that I could test this drive with, though I have a Zoomfloppy in the slow post and the 1541 test/demo disk in the post too.
Is there anything else I could try/test in the meantime to help get to the bottom of it ?
(I noticed reading in the drive manual it says that the disk is ejected by a small spring, but on this unit that is not happening, it just sits there when the handle is opened, so I'm am inspecting that now..I cannot see any mechanism in the drive that would cause the disk to spring out as suggested in the manual, the drive is a D500 made by Mitsumi Electric. The disk rotates and the head moves, but it tries to move to the disk perimeter where the motor appears to fight its end stop, then it returns to a position about 1/3 from the disk edge and stops, it never traverses the full width of the disk, but it will if I rotate it manually)
The drive itself looked almost NOS, has had little use, but it could still be defective.
When I attempt the use it, by typing N which sends the processor to D000h (where the ROM is), the error DRIVE NOT READY 00 00 is reported on the display.
But prior to this the drive starts up, makes a number of noises and when it stops, the red LED on the drive body blinks rapidly. I have a new un-formatted disk in the drive. But because I cannot get past the initial error I cannot format it.
So it appears the drive is responding initially, but in some way not working. (I have the disk inserted correctly and the drive handle closed)
I don't have any other computer that I could test this drive with, though I have a Zoomfloppy in the slow post and the 1541 test/demo disk in the post too.
Is there anything else I could try/test in the meantime to help get to the bottom of it ?
(I noticed reading in the drive manual it says that the disk is ejected by a small spring, but on this unit that is not happening, it just sits there when the handle is opened, so I'm am inspecting that now..I cannot see any mechanism in the drive that would cause the disk to spring out as suggested in the manual, the drive is a D500 made by Mitsumi Electric. The disk rotates and the head moves, but it tries to move to the disk perimeter where the motor appears to fight its end stop, then it returns to a position about 1/3 from the disk edge and stops, it never traverses the full width of the disk, but it will if I rotate it manually)
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