Update: BOOT ERROR DC – the plot thickens……..
The BOOT ERROR DC message is supposed to be caused by three things:
- Bad floppy disk
- Bad DC board
- Bad disk drive
In order to start eliminating/ruling things out, I sent two boot disks that I’d made from images to ChuckG who tried the disks in his Model 16. They both worked in his Model 16, so it isn’t the disks.
I also sent ChuckG my DC board, and he tested that in his Model 16, where it worked fine, so it isn’t the DC board either.
I tested my Shugart drive. It can make a disk from an image (using TeleDisk), and I can then get a directory of that disk (using22Disk). There’s still a problem with the drive though. As soon as I eject the disk, and re-insert it, I can no longer get a directory of the disk which is probably due to a disk centering/clamping problem. I’m going to swap out the hub clamp assy and spindle hub assy along with their bearings and see if that fixes it.
But when it comes to the Model II, it isn’t a disk drive problem either.
ChuckG modified the DC board I sent him, to allow it to boot from a 3 ½” floppy drive.
It works on his Model 16, but on my Model II the 3 1/2" drive is accessed, then the in-use LED lights, and that is followed by a BOOT ERROR DC message. So, I suspect there’s something other than the three problems that are listed in the troubleshooting section of the Model II service manual. I suspect it’s either the backplane (on which I have already reflowed every solder joint), or the CPU board.
Many thanks to ChuckG for the testing/modifications - who else would have been able to figure out how to, or that you even could, boot a Model II from a 3 ½” drive?
SoupWizard has generously shipped me a backplane and the four other boards from a Model II parts machine he had, so I can do some swapping around of boards to see what’s what.
I’m getting there – I’m just not sure where there is.