A1200 IDE Bus questions

[xaccrocheur]

OK now this one :

Why are IDE ribbon cables for the A1200 So damn expensive ?
That's 20£ for just a SINGLE IDE HD !

My question is :

# What the hell is this connector ? I mean the IDE-ATAPI one on the 1200 MoBo ? It seems shorter than a PC one...

# Is'nt there a way of building it using an existant PC AT (X) Connector, only by cutting it at the right lengh ?

This HD was sold with the machine, a Commodore 1200. It's a TINY WesternDigital CaviarLite 200. No wonder those stuff costed a lot and were not speed monsters.

What I vividly recall is that the salesman, a guy who seemed to knew the Amiga, when he installed the said drive in my machine, casually ripped off one red wire on one side of the ribbon cable.


_________________________
_________________________ <= plastic connector (44holes)
: : : : : : : : : : : : : : : : : : : : : :   : :  <= pins on the drive (44 + 4)

# What is this red wire stuff ?
# Why is that not ALL the drive's pins are plugged to the cable ? (if there is no answer to this one that's OK)

# Is that WD 200 drive (that says "AT Compatible, "A" standing for Amiga, I guess:) Special in any way ?

And the final, importantissimme question :

# What should I do to a regular PC AT  IDE Ribbon cable, to fit it on a 1200 MoBo ??

And the not as important as the previous :

# How to fit a 3.5 drive neatly in a desktop A1200 ?
# Is the latency problem experienced when a drive "starts" and is not spinning at full speed when the system needs it, always around ? I mean, I suppose that nowadays ALL HD manufactured after 1997/98 have a short latency, right ?

Thank you very much for the ligh

pX


pX

[xeron]

xaccrocheur wrote:
Whay are IDE ribbon cables for the A1200 So damn expensive ?
That's 10£ for just a SINGLE IDE HD !

Because its a non-standard cable.

 What the hell is this connector ? I mean the IDE-ATAPI one on the 1200 MoBo ? It seems shorter...

Its a connector for laptop (2.5") hard disks.

Is'nt there a way of building it using an existant PC AT (X) Connector, only by cutting it at the right lengh ?

Yes. You need a 44pin high density connector, a 40 pin high density ribbon cable, a 40 pin low density ribbon cable and a 40 pin low density connector. Put the connectors on the ends of the ribbon cables, and then strip and individually connect all 40 conductors of each cable.

That HD was sold with the machine, a Commodore 1200. It's a TINY WesternDigital CaviarLite 200. No wonder those stuff costed a lot and were not speed monsters.

Its a laptop HD.

What I vividly recall is that the salesman, a guy who seemed to knew the Amiga, when he installed the said drive in my machine, casually ripped off one red wire on one side of the ribbon cable.

This can fix some problems with some drives, but is not recommended unless you have the specific problem this is supposed to fix (and i cant remember what that problem is

 Why is that not ALL the drive's pins are plugged to the cable ?

If its a laptop HD, all 44 pins should be connected at both ends. If its a standard 3.5" drive, only 40 should be connected, as it gets its power from a seperate 4-pin connector (usually tapped into the floppy power supply in an A1200).

What should I do to a regular PC AT  IDE Ribbon cable, to fit it on a 1200 MoBo ??

See above.

[KennyR]

Whay are IDE ribbon cables for the A1200 So damn expensive ? That's 10£ for just a SINGLE IDE HD !

Because they're usually custom made. Normal IDE cables aren't so cheap either - they're about £7.50 each.

# What the hell is this connector ? I mean the IDE-ATAPI one on the 1200 MoBo ? It seems shorter...

44-pin IDE, designed for 2.5" (laptop) drives.

# Is'nt there a way of building it using an existant PC AT (X) Connector, only by cutting it at the right lengh ?

It's possible, but not worth the trouble you'd have with it, unless you are a professional at splicing cables. Not to mention the fact that the normal IDE cable is just a little bit more expensive, and you run the risk of just wasting it.

# What is this red wire stuff ?

A control line your Amiga doesn't need. More often that not it won't allow you to boot from cold if it's not removed - AmigaOS doesn't allow much time for HD spinup, and taking off this wire mean it won't bother waiting.

# Why is that not ALL the drive's pins are plugged to the cable ?

I take it the guy who fitted the cable used a 40 pin plug (for ease), but the A1200 IDE has 44 pins. The extra pins aren't needed anyway.

Is that WD 200 drive (that says "AT Compatible, "A" standing for Amiga, I guess:) Special in any way ?

No! AT is an old PC family of motherboards. It just means the drive will work in a PC.

# What should I do to a regular PC AT IDE Ribbon cable, to fit it on a 1200 MoBo ??

Get a buffered 4-way IDE interface. It'll save you a hell of a lot of trouble.

# How to fit a 3.5 drive neatly in a desktop A1200 ?

You don't. Even a slimlime drive will be a bugger to fit and will cause the A1200 case to bulge. A1200s were designed for 2.5" drives. Though most of us got a 3.5" in, it's a kludge and isn't so pretty.

[xaccrocheur]

Get a buffered 4-way IDE interface. It'll save you a hell of a lot of trouble.

Mm. My retailer (the last 1 in Fr) does'nt do them anymore because "the price kept getting higher, get a Pegasos, now go away :-D "

So it's gonna be simple : A laptop ribbon cable to a *single* BIG IDE HD, and YES I know I will need more power 4 that.
I'm actually building a 250W Amiga PSU with an old AT one. :-) So it *will* be buldgy anyway. Heck, maybe I won't even bother to put the drive in it and secure it outside with some gaffer. This machine is a game-only AGA machine, no flame

pX

> I take it the guy who fitted the cable used a 40 pin plug (for ease), but the A1200 IDE has 44 pins. The extra pins aren't needed anyway.

The extra 4 pins are power. 2.5" HD's get their power directly from the ribboncable but 3.5" HD's consume too much power to be able to do that. They need to get power elsewhere.

>> # Is'nt there a way of building it using an existant PC AT (X) Connector, only by cutting it at the right lengh ?
> It's possible, but not worth the trouble...

This is NOT possible! A standard AT connector for 3.5" HD's have 2.54mm (0.1") between ever pin. The high density 2.5" connector has 2.00mm between every pin and thus they can't fint at all.

>> # What is this red wire stuff ?
> A control line your Amiga doesn't need. More often that not it won't allow you to boot from cold if it's not removed - AmigaOS doesn't allow much time for HD spinup, and taking off this wire mean it won't bother waiting.

This is the IDE reset-line. Some 2.5" HD's spin down when they get the reset. The Amiga sends reset when rebooted which means that such a drive would spin down and up every time the computer is rebooted which is devastating for the drive and it take longer time to reboot. In these cases one may cut the red wire.