Prepping compactflash as IDE drive

[rare_j]

My CF- IDE converter should be arriving in a few days (£5 off ebay, bargain fans), is there anything I should be aware of, settings wise? In hdtoolbox, I mean. Should I just go with the defaults from "read drive geometry"? The reason I ask is because I looked up a thread where someone mentioned maxtransfer for these devices, but didn't say what it should be set to!

It's only a 64MB card but should do nicely enough for a boot drive that I don't write to too regularly. Silent as well.

[thomas]

Set MaxTransfer to 64k, this works with any drive. Problems only arise if it is too high.

[rare_j]

0x0001FE00 = 128K
0x0000FFFF = 64K

thanks

[thomas]

Originally Posted by rare_j

0x0001FE00 = 128K
0x0000FFFF = 64K

0x20000 = 128k
0x10000 = 64k

0xffff = one less than 64k
0x1fe00 = 512 less than 128k

[rare_j]

Well I stand corrected, I'd been led to believe those values were represented by that code but it just goes to show you can't believe everything you read on the net.

[amethyst]

My 256Mb Viking CompactFlash card (that I got from Amazon.co.uk) wouldn't format although PrepCard is able to detect it as a Toshiba manufactured card. Is there a maximum size limit to CF cards in the PCMCIA port? Maybe 256Mb was too big and it can only take 128Mb max.

I also tried it with an CF-IDE adapter too and it wouldn't work through that either.

[thomas]

@amethyst: you are off-topic.
PrepCard can only be used for RAM cards. For CF cards you need the cfd driver from Aminet and use HDToolbox to initialize it as an Amiga HDD or FAT95 to share files with a PC. The only size limit I know of is 4GB.

[thomas]

Originally Posted by rare_j

Well I stand corrected, I'd been led to believe those values were represented by that code but it just goes to show you can't believe everything you read on the net.

There are two philosophies playing into these values: one says that it is better to use the highest value which is smaller than the desired size (i.e. 0xffff aka 65535 is the higest value less than 64k aka 65536). And the other one says that the value should be divisible by the (physical) block size. E.g. 0xfe00 aka 65024 is the highest value which is smaller than 64k and divisible by 512 aka 0x200.

[rare_j]

Thanks for the clarification there Thomas.
The CF>IDE adapter arrived and it all works well on it's own. I just took the default settings form HDToolBox and set maxtransfer to 64k.

I've got a problem now with idefix, I load idefix to access my old hard disk and zip drive on the secondary IDE channel (I've got one of those buffered IDE splitters) but when I do the CF card stops altogether and hangs when I try to access it. The hard disk comes up fine!

Any idefix experts know why it would hang up a CF card in an IDE adapter? Perhaps it thinks it's a removable drive or something?

[thomas]

Not really an expert, but you should run IDEfixPrefs and check the options. If there is something related to auto-mounting LS120 or ZIP drives or similar, you should disable it.

[rare_j]

The settings in IDEFIX have no reference to automounting zip or LS120 specifically, but there is some preferences as for auto detecting the device and auto mounting it. Combinations of settings yeilded no results though, so I had to give up. I have to assume that idefix for some reason cannot handle the compactflash as an IDE device. If someone has had this working I'd be interested to know.

Later I remembered I had a disk with elbox's 4xeide.driver software on (which came bundled with the splitter hardware) and tried that instead. It seems to work in that it doesn't hang the machine with a CF card, although I have done no heavy data transfers yet. It's got no specific support for zip drives like the idefix has (ejecting disks doesn't register with the until you try to access them) but it does at least work with the CF card.

[alexh]

IDE commands (Pre ATA6) have sector count field which is 8-bits wide. This limits the maximum number of sectors in a single command to 255*.

With the standard block size of 512 bytes this gives IDE a maximum transfer value of:

255*512 = 0x1FE00

* Yes I know that 0 can represent 256, but it is a special case

[asm1]

Originally Posted by rare_j

The settings in IDEFIX have no reference to automounting zip or LS120 specifically, but there is some preferences as for auto detecting the device and auto mounting it. Combinations of settings yeilded no results though, so I had to give up. I have to assume that idefix for some reason cannot handle the compactflash as an IDE device. If someone has had this working I'd be interested to know.
card.

Welcome to my world of pain (see my thread on Idefix and other related woes)

It (idefix, or rather the software) doesn't like the CF/Microdrive as an IDE device as you have discovered, yet on a HDD it installs and works flawlessly.