Ampro Little Board Plus Fired Up--Now for a HDD

[saundby]

I have an Ampro Little Board Plus that's been sitting in a box since Dave Baldwin gave it to me some time ago. Tonight I finally hooked it up to a power supply, drives, and a terminal and whaddayaknow...it came up just fine, once I got the drives, jumpers, power supplies, cables, etc. sorted out. Not a huge project but something to keep me busy while I'm collecting up parts to get the Ferguson BBI he gave me set up properly (how I wish I'd subscribed to MicroC earlier, now!)

The long version is on my blog.

Anyway, now I want to get a hard disk on it. The docs say it'll use anything SCSI up to 88MB. My low capacity SCSI drives are already spoken for in other systems. I've got a couple of old ST-506 MFM drives of about 40-60MB that are free, I could probably find an Adaptec 4000 or something, but it'd be nice if I could do with what's on hand.

So, the question is, can I use a SCSI hard disk larger than 88MB and what would it take to make it work? I have plenty of other SCSI-1 SE drives around. Frex, could I put in a 120MB and just format it for less? Or could I edit some constants and format the drive then?

As for buying a small SCSI disk, the ones most plentiful on the net are old Mac drives. I seem to recall there's something different about the Mac SCSI controllers--changes in the standard command set or something. Or do they implement at least the required SCSI commands, enough so that I could expect to use them?

Your thoughts, suggestions, experiences are welcome.

Thanks,

Mark

 

[saundby]

I got the basic two-drive system moved into a box tonight and took a look at the source code for the Ampro hard disk utilities. I wanted to see if there was anything in the software that would cause the 88MB hard disk size limitation that Ampro calls out in their documentation.

At a quick look, I didn't see anything that should limit it to 88MB. It looks like the "Generic" or "Seagate" procedures should be able to read the disk's info about its configuration OK via standard SCSI commands and format the disk. The number of 8K blocks looks like it would limit disk size to about 500MB (blocks are tracked in 16 bits.) Other than that I'm not seeing any specific size limitations.

At any rate I think I'm going to drop in one of the >80MB SCSI drives I've got on hand sometime in the next few days and see what happens. I'm also planning on setting up a couple of 3.5" drives.

If anyone has any thoughts or experiences to pass along, they'd still be appreciated.

Thanks,

Mark

 

[jackrubin]

Hi Mark,

I'm interested in your Ampro adventures. As I read your post, it sounds like you're planning to try to hook up a SCSI drive directly off the 50 pin header on the Ampro motherboard. Did I understand correctly? I was wondering about doing something similar. The Ampro hard disk manual talks about a series of SCSI-MFM controllers but nothing about straight SCSI. What I'm really thinking about is using the SCSI interface to a SCSI-IDE bridge with an IDE drive or CF card. Do you have the hard disk software? Version 3 boot ROM?

No point in wasting time with MFM drives. Please keep us current on your progress.

Thanks,
Jack

 

[saundby]

I've got a 50 pin SE SCSI-2 drive hooked up to the system that's working great. I'm using 88MB of a 1.1GB drive. Most of it is yawningly empty, I've installed nothing but the ZCPR and CP/M stuff from the Ampro disks, and Turbo Pascal 3.01. I have one drive/user are dedicated to Assembly language, and another to Pascal.

Here's my most recent blog entry on this system:
http://catsonkeyboards.blogspot.com/2009/08/retrocomputing-with-cpm-and-only-cpm.html

I've got a nice enclosure lined up for this system now, but getting it into it has been delayed by time constraints on an 8085 SBC project I'm currently working on (http://saundby.com/electronics/8085/.) I'm hoping to finish that project over the next couple of weeks then find time to get the Ampro into its attractive new box by Christmas.

The larger SCSI HDD is working out just fine in the Ampro. It runs cooler than the older drives and is self-parking. I also have plenty of drives of this sort around, whereas I've only got a very few drives <88MB, and those are all in use and not SCSI.