Seagate ST-238 interleave

[Guest]

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

Yes, this is an ancient drive! Sue me, I collect vintage computers.

Anyway, I recently picked up a Compaq Portable with an ST-238 that
wouldn't boot, so I did the old WD ROM debug command g=c800:5, which
kicked me into the controller BIOS.

When it asked me what interleave to use (currently set to 4) I said
"what the heck" and entered 1. After a long time, the low-level format
finished, and I did the usual fdisk & format.

Here's the weird part: I ran Nortons SI, and the disk rating (compared
to a standard PC hard drive) was 0.5! That's ridiculous for a -238. I
fired up the debug routine again, thinking I would change the
interleave to 2 or maybe 3, when the routine said (again!) that the
drive was currently at a 4-1 interleave. What happened? I aborted the
routine without changing anything.

Now, it's been a loonnnng time since I messed around with rll drives,
but maybe this controller threw out the selected 1-1 interleave? It's
an 8-bit WD controller, not 16-bit.

Also, I'm pretty fuzzy on this stuff now. Does anyone remember the
optimal interleave for an 8-bit rll controller? Now that I think about
it, 3-1 comes to mind. I think you needed a faster 16-bit controller
to use 1-1 effectively. When you could, it kicked ass.

Comments? TIA!

P.S. Anyone know where I can find a working Epson QX-10 that won't
cost me an arm and a leg? I saw one for sale for $90 a couple months
ago, but I didn't move fast enough.

 

[Guest]

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

I also remember 3:1 for some reason.


"Casey Tompkins" <ctompkins@cinci.rr.com> wrote in message
news:5e9db010ldgo0gi8ss12bsk34ktk2sorvg@4ax.com...
> Yes, this is an ancient drive! Sue me, I collect vintage computers.
>
> Anyway, I recently picked up a Compaq Portable with an ST-238 that
> wouldn't boot, so I did the old WD ROM debug command g=c800:5, which
> kicked me into the controller BIOS.
>
> When it asked me what interleave to use (currently set to 4) I said
> "what the heck" and entered 1. After a long time, the low-level format
> finished, and I did the usual fdisk & format.
>
> Here's the weird part: I ran Nortons SI, and the disk rating (compared
> to a standard PC hard drive) was 0.5! That's ridiculous for a -238. I
> fired up the debug routine again, thinking I would change the
> interleave to 2 or maybe 3, when the routine said (again!) that the
> drive was currently at a 4-1 interleave. What happened? I aborted the
> routine without changing anything.
>
> Now, it's been a loonnnng time since I messed around with rll drives,
> but maybe this controller threw out the selected 1-1 interleave? It's
> an 8-bit WD controller, not 16-bit.
>
> Also, I'm pretty fuzzy on this stuff now. Does anyone remember the
> optimal interleave for an 8-bit rll controller? Now that I think about
> it, 3-1 comes to mind. I think you needed a faster 16-bit controller
> to use 1-1 effectively. When you could, it kicked ass.
>
> Comments? TIA!
>
> P.S. Anyone know where I can find a working Epson QX-10 that won't
> cost me an arm and a leg? I saw one for sale for $90 a couple months
> ago, but I didn't move fast enough.
>

 

[Guest]

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

Casey Tompkins <ctompkins@cinci.rr.com> wrote in message news:<5e9db010ldgo0gi8ss12bsk34ktk2sorvg@4ax.com>...

> Compaq Portable with an ST-238 that wouldn't boot, so I did
> the old WD ROM debug command g=c800:5,
> When it asked me what interleave to use (currently set to 4)
> I said "what the heck" and entered 1.

> I ran Nortons SI, and the disk rating (compared to a
> standard PC hard drive) was 0.5! That's ridiculous
> for a -238. I fired up the debug routine again, thinking I
> would change the interleave to 2 or maybe 3, when the routine
> said (again!) that the drive was currently at a 4-1 interleave.
> What happened? I aborted the routine without changing anything.
>
> Now, it's been a loonnnng time since I messed around with rll drives,
> but maybe this controller threw out the selected 1-1 interleave? It's
> an 8-bit WD controller, not 16-bit.
>
> Does anyone remember the optimal interleave for an 8-bit rll
> controller? Now that I think about it, 3-1 comes to mind.
? I think you needed a faster 16-bit controller to use 1-1
> effectively. When you could, it kicked ass.

I don't remember the lowest interleave those WD controllers would
accept, but 4 was optimum for 8-bit machines, anything from 5-6 was
optimum for 16-bit machines (they either did 8-bit transfers slower or
the DMA didn't work).

An old DOS utility called HDTST128 will let you find the best
interleave and change the current interleave.

 

[overlord]

Archived from groups: alt.comp.hardware.pc-homebuilt (More info?)

Seems I recall the old Spinrite would test the drive to find the optimal
interleave values for data transfer speed....

On Fri, 28 May 2004 02:45:04 GMT, Casey Tompkins <ctompkins@cinci.rr.com> wrote:

>Yes, this is an ancient drive! Sue me, I collect vintage computers.
>
>Anyway, I recently picked up a Compaq Portable with an ST-238 that
>wouldn't boot, so I did the old WD ROM debug command g=c800:5, which
>kicked me into the controller BIOS.
>
>When it asked me what interleave to use (currently set to 4) I said
>"what the heck" and entered 1. After a long time, the low-level format
>finished, and I did the usual fdisk & format.
>
>Here's the weird part: I ran Nortons SI, and the disk rating (compared
>to a standard PC hard drive) was 0.5! That's ridiculous for a -238. I
>fired up the debug routine again, thinking I would change the
>interleave to 2 or maybe 3, when the routine said (again!) that the
>drive was currently at a 4-1 interleave. What happened? I aborted the
>routine without changing anything.
>
>Now, it's been a loonnnng time since I messed around with rll drives,
>but maybe this controller threw out the selected 1-1 interleave? It's
>an 8-bit WD controller, not 16-bit.
>
>Also, I'm pretty fuzzy on this stuff now. Does anyone remember the
>optimal interleave for an 8-bit rll controller? Now that I think about
>it, 3-1 comes to mind. I think you needed a faster 16-bit controller
>to use 1-1 effectively. When you could, it kicked ass.
>
>Comments? TIA!
>
>P.S. Anyone know where I can find a working Epson QX-10 that won't
>cost me an arm and a leg? I saw one for sale for $90 a couple months
>ago, but I didn't move fast enough.
>

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