Disk II Controller

Anthony Adverse

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Oct 26, 2018, 9:37:47 PM10/26/18

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I have 2 of these, both of which are incomplete and a selection of Proms to play with. Does anyone know how to identify prom p5 and prom p6?

I have Apple 341-0028-01
Apple 341-0010-00
Apple 341-0009-02

TIA,

A

Patrick Schaefer

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Oct 27, 2018, 9:37:56 AM10/27/18

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Am 27.10.2018 03:37 schrieb Anthony Adverse:

> I have Apple 341-0028-01
16 Sector drive controller P6A ROM

341-0027 would be 16 Sector drive controller P5A ROM

> Apple 341-0010-00
13 Sector drive controller P6 ROM

> Apple 341-0009-02
13 Sector drive controller P5 ROM

Patrick

Anthony Adverse

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Oct 27, 2018, 5:33:28 PM10/27/18

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Is it possible to clone these things? I don't think 13 Sector is going to help me much :( So I'm on the hunt for 2x 0027 and 1x 0028..

Thanks

giorgio....@alice.it

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Oct 28, 2018, 2:08:45 AM10/28/18

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Il Sat, 27 Oct 2018 14:33:27 -0700 (PDT), Anthony Adverse
<the.e...@gmail.com> ha scritto:

>Is it possible to clone these things? I don't think 13 Sector is going to help me much :( So I'm on the hunt for 2x 0027 and 1x 0028..
>
>Thanks

Hallo Antony
I am looking for prom for 13 sector.
I can send you a new 16 sector card.

I am living in Italy.
Ciao
Giorgio

Apple II and Apple III forever !!!

Anthony Adverse

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Oct 28, 2018, 2:43:43 AM10/28/18

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All the way from Australia... do want an entire card or just the roms? Happy to swap...

Anthony Adverse

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Oct 28, 2018, 3:36:09 AM10/28/18

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On Sunday, October 28, 2018 at 5:08:45 PM UTC+11, giorgio....@alice.it wrote:

Actually just so we're crystal.

I can't guarantee these proms work. They aren't in a card, and I don't have a spare card to try them in. If that's ok, I'm happy to swap, your welcome to one of the controller cards if required. It is missing a number of 74 series chips as well as the proms though.

If we're good mail sysop.at.tlp.zapto.org

A

groink_hi

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Oct 29, 2018, 8:01:48 PM10/29/18

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Instead of attempting to convert the Disk II controller to 13-sectors with PROMs, I'd instead buy the MicroSCI disk controller, or the Franklin Ace disk controller. They're virtually the same. There's a jumper setting on the card that can switch between 16-sector, 13-sector and diagnostics.

There's also a controller called "NOC Dual Drive Card" which auto detects the type of disk in the drive, and boots accordingly. I have three of these cards.

There's also a cool DOS 3.3 patch in Nibble magazine called "DOS 3+2" which allows you switch between 16 and 13-sectors in DOS. I had "DOS 3+2" installed on all of my boot disks.

James Davis

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Oct 29, 2018, 9:25:54 PM10/29/18

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I don't recall, but was there a problem with the 13-sector PROM floppy disk controller cards not being able to read 16-sector floppy disks without upgrading to the 16-sector PROMs? Or could it be circumvented via boot-up-sector code?

Steve Nickolas

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Oct 29, 2018, 11:13:32 PM10/29/18

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On Mon, 29 Oct 2018, groink_hi wrote:

> There's also a cool DOS 3.3 patch in Nibble magazine called "DOS 3+2"
> which allows you switch between 16 and 13-sectors in DOS. I had "DOS
> 3+2" installed on all of my boot disks.

There's a patch called "DubbelDOS" that I think was written by a regular
from here back in 1981 that enables DOS 3.3 to read DOS 3.2 disks,
switching RWTSes automagically.

There's something I've seen used, but haven't found an installer for, that
allows you to create a DOS 3.1 or 3.2 disk that boots automatically on
both a 13-sector and a 16-sector drive. (Castle Wolfenstein uses this
with a protected DOS 3.1; some early DLM disks use this with DOS 3.2.)

-uso.

Michael J. Mahon

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Oct 30, 2018, 2:02:42 AM10/30/18

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That’s correct. The state machine PROM had to be upgraded to handle
16-sector disks, and could also read 13-sector disks. Only the boot code
needed to be switched for the appropriate disks, and if booting was
controlled by software, not the Controller PROM, it could choose which to
boot.

The BASICS preboot disk was an example of using software to boot a
13-sector disk with a 16-sector controller.

Frankly, 13-sector disks are so rare that it’s hard to justify any hardware
provision for booting them.

--
-michael - NadaNet 3.1 and AppleCrate II: http://michaeljmahon.com

James Davis

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Oct 30, 2018, 12:55:09 PM10/30/18

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On Monday, October 29, 2018 at 11:02:42 PM UTC-7, Michael J. Mahon wrote:
> ... 13-sector disks are so rare ....

I still have a few of them, original masters and backup copies.

waynej...@gmail.com

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Oct 30, 2018, 3:48:50 PM10/30/18

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Have a couple as well but it's been years since I used one. If needed I have a couple of disk controllers with jumpers and a few controllers that sense whether a disk is 13 or 16 sector and automatically boot

Michael J. Mahon

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Oct 31, 2018, 3:43:15 AM10/31/18

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...and I’ll bet that it’s actually no real inconvenience to use a preboot
(like BASICS) to boot them. ;-)

There was a couple-year period in which many users needed frequently to
boot both disk types, but these days, that’s just a memory for most.