tsp@hadron.UUCP (T. Scott Pyne) (03/21/86)
References: [] A possibly naive question for the net: when formatting an ST506 Winchester, in this case a Tandon TM502 in a Tandy 2000, does (can) the formatting program know, or have to know, beforehand how big the disk in question is? I am interested in swapping the 10Mb disk in my 2000 for a larger (35Mb? 70Mb?) disk, still mounted internally. The HFORMAT program which comes with MS-DOS on the 2000 seems to have an idea how many cylinders there are on the disk (of course), so what happens when I power the system up with, e.g., a 35Mb disk? Does the formatter find out that the disk is 35Mb and work OK? Failing that, does one have to hardwarily tell the controller how big each attached disk is? Tandy, of course, supports only an external add-on disk, but the disk driver in Venix doesn't understand about multiple disks yet. Anyway, all enlightenment is gratefully accepted. If I get a slew of responses (or requests for forwarding of information), I'll post a summary. Thanks in advance. Scott ========== T. Scott Pyne Hadron, Inc. ...!seismo!hadron!tsp tsp@hadron.UUCP
bmw@aesat.UUCP (Bruce Walker) (03/25/86)
In article <321@hadron.UUCP> tsp@hadron.UUCP (T. Scott Pyne) writes: >[...] when formatting an ST506 >Winchester, in this case a Tandon TM502 in a Tandy 2000, does (can) >the formatting program know, or have to know, beforehand how big the >disk in question is? I am interested in swapping the 10Mb disk in >my 2000 for a larger (35Mb? 70Mb?) disk [...] >so what >happens when I power the system up with, e.g., a 35Mb disk? Does the >formatter find out that the disk is 35Mb and work OK? [The follwing remarks pertain to PC (& PClone) compatible controllers] The hardware (controller) itself knows how big the disk it controls is. The disk controller's firmware ROM has a four entry table which contains values for such esoterica as: number of cylinders, # of heads, where the write precomp should start (if any), etc. A set of DIP switches or (more usually) plug jumpers on the controller board is consulted during the POST (Power-On Self Test) to determine what sizes of drives are attached. Now, it starts getting tricky. The sequence for formatting (on a stock PC) is as follows: "hard" format using the Advanced Diagnostics disk; set up partitions and a boot block with FDISK; finally "soft" format with FORMAT. I differentiate between "hard" and "soft" formatting because the DOS FORMAT program is badly named (at least for its role with hard disks). It does *not* format the hard disk, it reads all the sectors (which must have been *pre*formatted), zeroes the FAT, marks bad clusters in the FAT, and zeroes the directory area (in UNIX parlance, it is like "mkfs(M)" ). On other DOS'es, the names are changed to protect the guilty (and confuse the innocent), but the sequence is the same. The hard format program is required before any disk can be used. It can format any size disk (within the capabilities of the controller itself). Depending on the version of DOS, FDISK can partition different amounts of disk - PCDOS 2.1 can only handle about 32Mbytes while 3.1 can handle up to (approx) 130 Mbytes. With the "standard" DOS disk drivers, however, a DOS partition may only be up to 32 Mbytes (with any version of DOS). Some third-party large disk vendors supply new disk drivers which allow very large partitions and / or multiple "logical" drives to get DOS to handle up to the 130 Meg capabilities of the drives. So, to alter your system to take a bigger drive, you may have to get a new disk controller ROM with the appropriate entry for the new drive size, and if it is bigger than 32 Meg, get a new driver to allow DOS to use it. Most controllers available today know how to talk to "standard" 20 Meg drives (typical half-height Seagates and Shugarts (225's & 725's), etc), so that combination is easily installed. However getting a 45 or 70 Meg disk to live in your system is much more of a trick (although, if your goal is to run a UNIX package, they may make your life easier by supplying configurable drivers). Bruce Walker {allegra,ihnp4,linus,decvax}!utzoo!aesat!bmw "I'd feel a lot worse if I wasn't so heavily sedated." -- Spinal Tap
mc68020@gilbbs.UUCP (Tom Keller) (03/29/86)
****** A R G H ******
**PLEASE** keep system specific questions and answers in the appropriate
newsgroups.
I have very carefully avoided learning anything about MessyDos, and the
Inherently Bogus Machine company's Piece of Crap. PLEASE confine discussion
of this parody of a computer to the net.micro.pc group!
Likewwise with other systems. I am a 68K fan. I don't want to see 68K
specific stuff here either!
--
====================================
Disclaimer: I hereby disclaim any and all responsibility for disclaimers.
tom keller
{ihnp4, dual}!ptsfa!gilbbs!mc68020
(* we may not be big, but we're small! *)apr@lzaz.UUCP (A.PROCTOR) (03/31/86)
I was very interested to read the reply to the original posting. It
spoke of using FDISK as part of the procedure to install a hard disk
on the Tandy 2000.
I have been trying to change the cluster size on my Tandy 2000, 10
meg hard disk for some time now, to no avail. The cluster size is
defaulting to 8K and causing me to waste half of my hard disk space!
(my average size file is 4K and using the minimum cluster size
wastes 4K everytime).
I have read on former postings on the net that installing my hard
disk with FDISK would automatically change my cluster size to 4K.
That's great, but the MSDOS 2.11 that comes on the Tandy 2000
doesn't seem to have the command FDISK. Did I miss something?
I have also tried the technical reference manual on MSDOS.
It speaks about a minimum allocation unit on the boot sector,
but changing this to half its hex value and re-formatting
had no effect.
Thank you for any help you can give.
Arnold Proctor
14 Lisa Ct RD # 1
Matawan, NJ 07747
(201) 576-2403jnl@inuxh.UUCP (John Le) (04/03/86)
>... > I have read on former postings on the net that installing my hard > disk with FDISK would automatically change my cluster size to 4K. > That's great, but the MSDOS 2.11 that comes on the Tandy 2000 > doesn't seem to have the command FDISK. Did I miss something? > >... > > Arnold Proctor > 14 Lisa Ct RD # 1 > Matawan, NJ 07747 > (201) 576-2403 Yes you DID miss something. FDISK is not on the MSDOS 2.11 disk. It should be on the SUPPLEMENTAL PROGRAMS DISK. If you don't have this disk when you buy the system, you are screwed.
garyk@techsup (04/04/86)
/* Written 2:08 pm Mar 21, 1986 by hadron.UU!tsp in techsup:net.micro.trs- */ /* ---------- "formatting ST506 winchesters (naive" ---------- */ References: the formatting program know, or have to know, beforehand how big the disk in question is? I am interested in swapping the 10Mb disk in my 2000 for a larger (35Mb? 70Mb?) disk, still mounted internally. ========== T. Scott Pyne Hadron, Inc. ...!seismo!hadron!tsp tsp@hadron.UUCP /* End of text from techsup:net.micro.trs- */ HFORMAT for the Tandy 2000 has a /p option that will cause the program to ask the user for the number of heads & cylinders. Gary Kueck trsvax!techsup!garyk Radio Shack Technical Support #0220
mikey@bbimg (04/08/86)
If tom keller doesn't like the PC, why doesn't he keep his rantings confined to net.micro.pc instead of posting to wildcard nets!! Mike Yetsko
bc@cyb-eng.UUCP (Bill Crews) (04/09/86)
I don't know much about this subject, but I do know that FDISK is a part of
PC-DOS that is IBM's, and isn't in MS-DOS.
--
- bc -
..!{seismo,topaz,gatech,nbires,ihnp4}!ut-sally!cyb-eng!bc (512) 835-2266