Gotek Floppy Emulator
With good floppy drives hard to come by, to say nothing of blank diskettes, an alternative is needed. A GoTek drive with Flash Floppy firmware update is capable of reading and writing disk formats as used by SK*DOS, REX and OS9. The GoTek uses USB memory sticks to store images of floppy disks and can hold thousands of disk images on a single USB stick. The images can be emailed as well as downloaded over the internet. We supply boot disk images for the GoTek, so you will need to have at least one GoTek in your system. GoTek's are available from Amazon for about $30; the Flash floppy firmware is free; an OLED display adds a few dollars but is a necessity so you can see the name of the disk you are selecting. Otherwise you are selecting the disks by a number and not by the name of the disk image.
As a service we will sell a modified GoTek for those not wanting to modify one. Updating the firmware voids the warranty of the GoTek, so the ones we provide will have no warranty.
The instructions for flashing the firmware and adding the OLED display can be found here - https://github.com/keirf/FlashFloppy/wiki
You may use a real floppy drive with a GoTek should you have a need to read or write real diskettes.
VGA Video Display Card/XT keyboard
The PT68K5 supported a VGA card with the TSeng LABS ET4000 chip set. Not all VGA cards with a ET4000 chip set will work in the PT68K5. If you purchase an ET4000 video card, ensure it can be returned should it not work in the PT68K5. TSeng LABS ET4000 cards are hard to find; but should you be lucky enough to own/find one, you will still need an XT keyboard. A converter card is available to allow an AT or PS/2 keyboards to be plugged into the XT keyboard port of the PT68K5. This card plugs into the J9 connector on the PT68K5.
OS9 hard disk drivers have been updated to support modern IDE drives. The original hard disk drivers don't work reliably with today's hard drives. The set parameters command doesn't seem to work well with drives that were made in the last 20 years, The IDE drivers was updated to support LBA mode of today's IDE drives. Older IDE drives that do not support LBA modes cannot be used.
A new (updated in 2021) OS9 Boot ROM is supplied. This ROM supports booting OS9 from modern drives and different partitions. This includes mechanical HD's, SSD, SD memory cards and compact flash memory. While we suggest 4MB partition sizes, partition size can be up to 8GB. This is possible because IDE drives use 512 byte sector sizes. Devices that use a 256 byte sector size will support 4GB partition size. The ROM update also allows booting from a XT IDE controller card. It is assumed that the XT IDE controller would be connected to an SD to IDE converter card and use SD memory cards. This is intended to provide for an easy and cheap backup of an SSD hard drive on the 16 bit internal IDE port. SD memory cards are readily available for about $5 for 32GB of storage space and are faster than hard drives of the 90's . The new hard disk drivers can coexist with the original drivers should you need to copy data from a old hard drive to a new one.
SD memory to IDE converter cards cannot be used on the 16 bit internal IDE port on the PT68K5. They can be used on the XT IDE controller card.
REX Operating System
For the moment REX is bootable on a compact flash 64MB card attached to the main 16 bit IDE port. REX can also be loaded from a GoTek image disk. There is no reason REX could not work on other disks for someone wanting to tackle this. But for now, REX is available preinstalled and bootable on one brand/size of a compact flash card. REX really needs to be updated to support LBA mode of modern drives. Of course full source code to the REX operating system is available should some of you wish to tackle this. REX does not currently support the XT-IDE controller.
Boot OS9 and REX on Hard Drive
Since drives are inexpensive, I don't recommend trying to partition a single drive between OS9 and REX. It is too easy to make a mistake that will destroy the other. Since REX can only boot from a hard drive configured as a "Master" on the internal 16 bit IDE port, you should boot OS9 from the "Slave" drive since OS9 can boot from either the Slave or the Master drive as well as the XT IDE controller.
Click Here for User Manual PT68K5 CD68X20 Users Manual
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|PT68K5||PT68K5 System Board,25MHZ 68020, 0K Memory - Very Limited availability||$599|
|ET4000-K5||ET4000 Video Card - Sold only with PT68K5 or recent PT68K5 purchases - Used - Extremely Limited Quantity||$149|
|PT-XTIDE-K5||IDE controller card, XT slot for PT68K5, Works only with OS9, no REX support||$39|
|K5-RS232/VGA/KBD||Use a VGA monitor and PS/2 keyboard on one of the RS232 Ports||$33|
|K5-RS232/VGA/USB||Use a VGA monitor and USB keyboard on one of the RS232 Ports||$33|
|K5-XT-AT||Plug in adapter board to convert on board XT Keyboard port to AT or PS/2 keyboard||$10|
|Add On items - The items below are only sold at the time of purchase of a PT68K5|
|MC68882||25MHZ Math Coprocessor for PT68K5||$20|
|4MBx8/6||16 MB - Four 4MB 60ns 30 Pin SIMM (32MB Maximum) Sold only with PT68K5 board||$25|
|4MBx8/6||64MB - Four 16MB 60ns 30 Pin SIMM (128MB Maximum) Sold only with PT68K5 board||$54|
|The flash floppy Firmware modification will void the GoTek warranty. The GoTek is sold without warranty|
|Gotek||GoTek Floppy emulator with Flash floppy firmware and OLED display - Sold only with PT68K5 purchase||$60|
|SSD HD||SSD 120GB Inland, Crucial, PNY or other major brand. OS9 preloaded||$30|
|Compact/Flash/REX||64MB Compact Flash Card with IDE Adapter, REX preloaded. The only current option for an HD boot of REX||$30|
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Click here for PT68K5 Brochure PT68K5 Historical Product Brochure
|OS9/68020||Professional OS9 V2.4 for PT68K5, Includes K&R C, Editor, Assembler, Linker, BASIC and over 80 utilities||$499.00|
|OS9/020U||68020 Upgrade from PT68K2/4 OS9/68000||$150|
|OS9/Ultra||Ultra C for OS9|
|CLIBV3.2||C Graphics Library for K&R V3.2 (Includes Source)||$50|
|CLIB-ULTRA||C Graphics Library for Ultra C (Includes Source)||$50|
|BASIC||BASIC for REX Operating System||$25|
|BASICSRC||Source Code for BASIC on 1.4MB Diskette||$20|
|TETRIS||Game - Requires OS9 and ET4000 VGA||$10|
|SCULPTOR||CloseOut - Version 1.14:6 (No support)||$50|
|REXSRC||Source for REX Operating System||$10|
Historical information on the CDS68020 and PT68K5
Early boards supported 2.88 MB floppy drives. The floppy controller chip, a SMC37C65+ was discontinued shortly after production of the CDS 68020 began. A few early boards had the SMC chip, but most shipped with a WD37C65 chip. The WD37C65 did not support 2.88MB drives. That is why there are references to 2.88MB drives in some of the literature. It was never fully edited out.
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