Reply to: When a 5Mb drive was big.

[Sysman]

I did that! Or something similar - IBM 3370 DASD disks, you needed good back muscles to hoick out the disks in order to change them.

The piccie was a Bull, though it might have been sold as a Honeywell Bull.

At one place they were struggling with French documentation, so Bull's answer was to provide French lessons.

That system was never going to work, but it was very political and so they kept it switched on but doing nowt.

I remember disk packs that size though. I had to carry them around various buildings at one point. It was easier to take two so you weren't walking lop sided.

Though that left bruises on your legs.

With all the stairs in those buildings as well I didn't need to pay for a gym.

[cojak]

This was mine;



You can tell it's a French computer, that bloke only has one thing on his mind!

I did that! Or something similar - IBM 3370 DASD disks, you needed good back muscles to hoick out the disks in order to change them.

[Doggy Styles]

zeity, did you ever get your hands on GEC 4000 machines? They were all the rage in higher education and scientific communities.

And Prestel.

And military.

[Sysman]

Oh yes, it was that there EBCDIC. Converting that to ASCII was the easy bit.

It was the figuring out of the directory information & stuff that was harder.

I did a lot of EBCDIC <--> ASCII conversions, but with tape and that was quite easy once you had worked out the tape labels. No directories involved of course.

[Sysman]

10MB cartridge & 10MB fixed platter?

We had a Dynex and a Wang drive that used those on a GA16-220 mini.

£5k per drive.

The double floppy system cost about £5k too.

The first ones were in an ICL 2903 and might have been only 5MB, but yes they were in a fixed platter plus removable cartridge combo.

Backing up the removable cartridge meant you had to backup and overwrite the fixed disk, then restore it.

What could possibly go wrong?*

The next disks I used were RK05 on a PDP, also in a fixed disk / removable cartridge combo. This time the fixed disk was double the density of the removable. 2.5MB/5.0MB IIRC.

* the answer to that question was the big boss who had signed the cheque for the machine would come in and run something out of order and bugger off when he realised he'd fecked things up, leaving me to do the restores.

[Ignis Fatuus]

Would that be that there Ebsy-Dick?

Or did IBM have some other format for floppies?

Yeah, spotted an account once with a balance of £40,404.04. Spent ages trying to find where the packed spaces came from but it really was the balance.

[Doggy Styles]

There's a reason for that.

I wrote programs on the GA mini that read IBM format floppies and changed them into proper ASCII, another program that read Intel MDS II ISIS format diskettes, and a program that read & wrote CP/M format diskettes.

I was a busy little bee in those faroff days.

Would that be that there Ebsy-Dick?

Or did IBM have some other format for floppies?

[Lockhouse]

This was mine;



You can tell it's a French computer, that bloke only has one thing on his mind!

[Doggy Styles]

Single sided single density 8" floppy: 250kbytes: 77 tracks, 26 sectors, 128 bytes/sector.

That seems to be engraved on my soul.

Double sided were 500k, but you needed a different disk drive to use them.

If you wanted to use SS & DS, you needed a special disk drive that had two index hole detectors.

Wonderful piece of design.

1.2M was the size of the HD 5.25" floppies on the AT.

PC XT used 320k DSDD disks, then 360k (extra sector).

Not sure if the PC used SSDD 160k disks.

Aha, my memory isn't as good as yours. It wasn't a PC though, it was a Tektronix 4xxx system we used occasionally for CAD.

[Ignis Fatuus]

WSS. And 512K RAM.

I got the full 640K - more than you'd ever need in real life.

[mudskipper]

Our 1st PC had a 20mb drive.

It cost us £1400...

WSS. And 512K RAM.

[cojak]

Our 1st PC had a 20mb drive.

It cost us £1400...

[Sysman]

I remember working with 8-inchers at some time or other. 1.2 megs I think.

The first disks I used were like these



which were 10MB and housed in a 19" cabinet

[NickFitz]

I remember working with 8-inchers at some time or other. 1.2 megs I think.

I used a 6809-based system with 8″ floppies for a few days when I started working at a digital systems engineering place, purely to get up to speed with polyFORTH. (They only kept those boxes around because some customers had old systems from them with that hardware, and for sticking junior engineers on before they let them loose on real work.)

[Doggy Styles]

'That's looks like a good size for the disk we want to make.' So it made it into the instructions for Shugart back in the Bay Area to make a floppy disk drive the size of a cocktail napkin—5.25 inches square.

And I have worked with Fujitsu Eagle drives (slide 13). If I remember correctly you could format them to look like 2 RM05 drives, might have been 3 with later models.

I remember working with 8-inchers at some time or other. 1.2 megs I think.