pegram@kira.UUCP (Robert B. Pegram) (06/21/91)
From article <2964@atari.UUCP>, by apratt@atari.UUCP (Allan Pratt): (floppy stuff omitted RBPIII).... > GEMDOS ... hard-disk partitions larger than > 16MB are implemented using large logical sectors (but not large physical > sectors) with appropriate values in the BPB. To use 1K sectors on floppies > you would have to replace the floppy BIOS completely, and include in your > TSR a routine which replaces GEMDOS's sector buffers with new buffers large > enough to handle the largest sector size in your system. This is what the > hard disk driver has to do (except that instead of replacing the floppy > BIOS it's installing the hard-disk BIOS). > > ============================================ > Opinions expressed above do not necessarily -- Allan Pratt, Atari Corp. > reflect those of Atari Corp. or anyone else. ...ames!atari!apratt I know, I know. I just switched from using an ICD adaptor to a BMS 200 adaptor on my Seagate 296N. BMS's ads are correct for my 1.5 year old 296N - ICD's RateHD now tells me that I get the (BMS) advertised 680 - 682KB/sec throughput that 1 to 1 interleave can give you. (Oh that dratted ICD tech "it depends on the (2XXN) drive, some work at 1-1, some don't" _BULL!_). ICD doesn't handle these tricky drives right, BMS does. In any case, a FAQ here has been "are ICD-Supra BGM partitions different from AHDI BGM partitions?" The answer is unfortunately, frequently yes. I couldn't completely restore my 32 Meg partition because the logical sector size went up and I lost about 3Meg of space (in tiny files). The ICD formatter had sensed that I had TOS 1.4 (and now 1.62) and allowed me to use the fixed-in-1.4-and-up _Unsigned_ count of total sectors for my < 32Meg (2^42 - 1 bytes) partitions with the logical sector size = to the physical sector size of 512 bytes. Berkeley uses AHDI and it does exactly the trick that Allan speaks of above. I assume that ICD and Supra do what he says for partitions greater than 16M with Tos < 1.4 and for partitions greater than 32M for Tos >= 1.4. My question: can I induce the Atari partitioner to do things the ICD-Supra way on my double sized partitions? If not, can I get Supra's formatter and use it with my non-Supra host adaptor (legally)? ICD's software checks for ICD HAs, so that solution is out. This situation is irritating because of the loss of space and because my favorite cache program won't work with BGM (logical <> physical sector size) partitions. It's Diamond Cache. I assume - but would like confirmation - that the Atari cache program will work, but it's less fun and less configurable. Some final BMS comments, I bought my Shoe Box off of Cove Systems, it's *very* nicely made (new back plate - mechanical stuff is well done - *keyed* scsi cables are supplied so you can't burn out the cable or even your disk <I've done both 8->), but as yet has no SCSI out connector, and is still _loud_. Any *good* suggestions on quieting a cheap Shoe Box? I managed to reformat and repartion my drive, but few drives are directly supported, and there is quite a mix of software involved. Lots of useless BMS 100 stuff is given with the new BMS 200 and AHDI stuff, I barely figured out what I needed. The docs were no help for embeded SCSI users, they need updating just as badly as the software. I'll have a big headache formatting my next drive, and will need help of some sort. Perhaps Cove got a deal on older stock? Since I finally set up an "OOP" partition for Spectre 3.0, I'm glad that I didn't need to create more than 4 partitions - Dave Small supports only the extended partitioning scheme of Supra-ICD and not the 2 tier system of AHDI. BTW, Dave, it's not my imagination, that mouse handler can occasionally completely freeze my keyboard on my new STe, as it did more frequently on my old 520ST. That machine got progressively worse and started to freeze up in ST mode! A new IKBD processor was no help and my trying to replace the ACIA was the death of old faithful. A friend with a Mega 2 also complains that this keyboard freeze happens from time to time... As an aside: It sounds like I'm a completely hopeless hardware hacker doesn't it? Actually I do fairly well and learn from my mistakes. When I insert the disk with the program I was using when the keyboard went south, and rerun the program in my now rebooted Spectre - it complains that the app is damaged or open. Come on Dave! Real Macs know if the disk was just inserted and whether Multifinder is in use, and fix this particular form of file system corruption silently. I know - I trashed my only system disks that way, and recovered them by simply copying them on a real Mac - the icons did change though. Moral of the Spectre: 8-) Folks, *ALWAYS* _COPY_ your system disks _in_Spectre_ *BEFORE* trying to use them the first time, else my problem could *easily* happen to you 8-(. (I forgot that this was possible - even with the floppy drive problems I was having) Sorry this got so *LONG* people, hope something comes of it 8-). ciao, Bob Pegram pegram@griffin.uvm.edu or ...!uvm-gen!pegram