macintosh classic hard drive not showing up.

Just a couple of questions to begin with. First of all, would it be correct to assume that it is the "real" Macintosh Classic, not just another classic Macintosh?

Could you perhaps let us know the make and exact model (and size) of the hard drive? Does it have an Apple logotype somewhere?

Is it a System 7.0.1 Disk Tools floppy or something else? Do you have access to other older Macintosh computers and/or SCSI accessories?

Hi,

It would help if you could provide the information about the hard drive model, etc.

Has the new hard drive been tested or (re)formatted using another Mac (and if so, by which formatting utility)?

Did the computer report a similar error when the older (broken) hard drive was used?

A Sad Mac error code like the one mentioned could per se indicate that something is wrong with the ROM, but the fact that the error does not appear when the hard drive is disconnected seems to point in the direction of a SCSI problem. In similar cases, one may want to remove/disconnect and reseat/reconnect memory modules and cables. Have you checked the hard drive configuration (jumpers?) and SCSI termination?

I assume that you know exactly what you are doing, but be careful. All work inside a compact Mac can be very dangerous because of high-voltage circuits, and must only be performed by someone with the necessary expertise.

Also, is it possible to boot from ROM (holding down the four keys Command=Apple + Option + X + O at startup)?

Has the drive been formatted properly?

It may not be a bad idea to double-check termination. Would the Quantum ProDrive that you have look like one of the models in the document http://www.seagate.com/staticfiles/maxtor/en_us/documentation/quantum_jumper_set tings/prodrive_scsi_jumpers.pdf? Normally, one would expect an original internal hard drive in a Macintosh Classic to have resistor packs. Is this the case with the ProDrive in question (if you wish to post a photo of the drive, someone here could possibly provide further information)? The standard SCSI ID for the internal hard drive is 0.

Hi,

The lower left part of the second picture (the new drive) would be of interest. It is difficult to see because of the light and the angle, but is there a text like A0, A1, A2 (or perhaps something else) and are there any connecting jumpers/clips? Normally, a SCSI ID 0 would mean no jumpers (connections in all three positions A0, A1, A2 would mean ID 7, which must not be used for a hard drive). Also, it looks like (two) resistor packs are in place; correct?

>yes. the old hard drive has that to.

?

Sorry, I do not follow you here. Do you mean that the new drive has A0, A1 and A2 positions? If so, are there any connecting jumpers in those positions?

The SCSI ID is normally not important as such, as long as no other device has the same number. The ID can be anything between 0 and 6, but the convention is that ID 0 is used for a single internal hard drive (that is, normally, no jumpers at all at A0, A1 and A2). If a hard drive had ID 7 (all three positions A0, A1 and A2 connected by jumpers), it would be in conflict with the computer itself (which has ID 7).

Any exact model number or text about jumpers on the other side of the hard drive?

>no I haven't put resistor packs in them. (bit of a no obligation with boards)

?

I meant resistor packs on the controller board of the hard drive itself. It looks like there are two (removable?) resistor packs parallel to the hard drive connector. That ought to be OK, but there should not be an additional terminator where the hard drive cable meets the logic board of the computer.

Hopefully, someone else here has more information, based on the photo of the new hard drive.