Storage type converters/adapters, what is available

[ParanoidLittleMan]

I saw here recently many threads where people want some storage type converter (sorry, can't come with better definition right now) .

The truth is that such things appeared on mass market only in this century. Surely reason is complexity, so it would be expensive to make in 1990, for instance.

What was launched in 1991 was ACSI/SCSI adapter made by Atari - in Mega STE and Stacy.  I  guess that ICD did it little earlier, and little later made much better one, without 1 GB space limit.  But, ACSI is actually early SCSI, done in time when some 100 MB counted as enormous capacity. So, conversion was not so hard.

 

What is today available is:  IDE-SD converter . And that's not simple thing. SCSI-SD - costs much more, probably only because lower sales.

IDE(PATA)-SATA converter, in both directions - when your motherboard have no PATA, just SATA, and want to connect some older IDE disk ... Opposite is rarer case, I guess.

USB-PATA - mostly to connect 2.5 inch external disks to PC .

USB floppy drive - it must have USB-floppy converter. And what is available is done with PCs in mind - therefore rigid format support - only 720, 1440 KB .

HxC, Gotek ... are basically converters floppy-SD card, or USB .

 

Atari specific: Satandisk, UltraSatan, Gigafile, CosmosEx . All it is for SD cards. And using extended ICD protocol to override 1 GB limit of ACSI.

 

There are diverse adapters available too, and they are mostly passive - just connectors connected internal.  Like IDE-CF adapters. Or 40 pin IDE-44 pin 2.5 inch disk compatible IDE (smaller) .

 

Why no SCSI-IDE converter ? I would say: low interest. IDE is de facto standard in home computers/PCs, so there is IDE port. Few thousands of people having oldie with SCSI and no IDE (here mean those who want to expand, experiment, use old drives) is not enough to spend lot of money on development and manufacturing.

 

 I really don't see why some people prefers complicated, expensive against simple ? Like this:  ACSI-SCSI, then SCSI-SD on it ?????

Sure, that's 'better' than straight ACSI-SD - because more is better ! Well, surely better for some sales. And that might be behind claims that UltraSatan works not with all STE (DMA chip problem affects all mass storage connected to STE) .

 

For the end:  why no ACSI-IDE converter for Atari ST ? There were plans to design it. By Jookie (Satandisk, UltraSatan designer), and by Techie Allison. It was around 2008-10. And both abandoned it. Partially because SD cards arrived and became more and more popular. Other reason is for sure complexity of such device. IDE differs a lot from SCSI/ACSI.

I'm who designed such thing (when made test circuit for measuring real speed of DMA chip (ACSI port), then realized that it can be used as base for converter/adapter). It is not real ACSI-IDE converter in fact.  It needs own driver, because using special commands, protocol. No autoboot from TOS, only if add special code for it. Works in 2 modes - fast, using DMA mode, and slow, using so called single byte mode of DMA.

Fast mode works only with Sandisk CF cards, because only them support 8-bit DMA mode. Speed is 1.9 MB/sec .

Slow mode works with all (good) CF cards, and it is PIO mode, what can be 8-bit with all (standard). Speed is 300 KB/sec, because need more commands to read 1 byte.

Will add new thread about it, since it will go in sale soon. Tori from Poland designed PCB for it, redesigned logic (now in CPLD), and it works very well.

I need to do more tests, to see work with different CF cards (so far Sandisk Ultra 4 GB, 25 MB/sec, shiny gray has problems with write, others work reliable) . And what needs lot of time: SW - new driver versions, autoboot code for diverse TOS versions. And it will be in iTOS too (already made working test version).