PDA

View Full Version : Macintosh SE "Bus Error"



int 21h
August 7th, 2012, 11:48 AM
Hi there,
I got ahold of a Macintosh SE that's been in storage for some time. When it powers on the "happy" Mac Face is shown, along with the "Welcome to Macintosh" message (the os is on a hard disk, I have no floppies or any other macs).
After that though, I get a message telling me there's a "bus error".
Does anyone know what is the cause of this?

NeXT
August 7th, 2012, 04:40 PM
See if it persists if you hold down the shift key while booting. Sometimes it's the result of an extension conflict or a drive that needs to be checked.

int 21h
August 7th, 2012, 11:48 PM
See if it persists if you hold down the shift key while booting. Sometimes it's the result of an extension conflict or a drive that needs to be checked.

Thanks for the reply!
I tried holding the shift key and it does say starting without extensions but the same error comes up :-(

RWallmow
August 8th, 2012, 03:52 AM
Thanks for the reply!
I tried holding the shift key and it does say starting without extensions but the same error comes up :-(
Could be as simple as a corrupt OS, or you could be looking at genuine hardware failure.

Not having any OS disks to test corrupt OS, you could try re-seating the RAM, and checking for blown or leaking capacitors (SE's are not as prone to "bad caps" as some newer "classic" macs, but it could happen). I would suggest you get some OS disks too, its very possible a corrupt OS is the only problem.

Not sure where you are located, but I am sure someone on here near by you could probably make you some OS disks (being an SE, I will assume its an 800k floppy, which means disks can ONLY be made on an older Mac, you cant image 800k disks on a PC or modern Mac). If you are in the US, I could make you a disk set for the cost of postage and disks, which I would estimate to be about $2-3 for media mail, or $5.35 flat rate priority and I would want about $0.25 a disk, because that's what I paid last time for some NOS DD 3.5 media (HD media is not real reliable when formatted to 800k).

If you have access to an older Mac with 800k compatible drive, the older MacOS images are available here (http://download.info.apple.com/Apple_Support_Area/Apple_Software_Updates/English-North_American/Macintosh/System/Older_System/), you could make your own set from there.

int 21h
August 8th, 2012, 09:58 AM
Hi again,
I live in Ireland so I'm a bit far away for postage but thanks for the offer! I know a guy here who might be able to copy the disks for me from his Mac so I'll ask him to do that!
If it is a hardware failure situation, where would the best place for me to find the problem be?
Just before the error shows you hard drive makes the same noise 3 times (the loading file noise heard on most hard disks)

Compgeke
August 8th, 2012, 10:09 AM
If it's the same repeating noise it's possible you have a failing hard drive. Another thing I can think of is if the drive isn't an original drive and doesn't have SCSI termination jumper on or no SCSI terminator on the end of the cable if the hard drive doesn't have a built in terminator.