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Which ROM is preferred for Kaypro 4/84?

clh333

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Advent TurboROM, MicroCornucopia or KayPlus?

Assuming I get one of the Kaypro 4/84s back to OEM spec I would like to then substitute one of these aftermarket ROMs to allow further modification of the system - mainly to augment drive capacity but also for the sake of greater utility. I have 27C64 EPROMs, an UV eraser and a GQ-4X programmer, as well as a source for the ROM code. I would have to create any support disks if I can find the source for them.

I'd like to hear anyone's opinions about which is easiest to implement, which has the best feature set, which is most bug-free, etc. Thank you for your replies.

-CH-
 
I have the PRO8 ROM from Micro Cornucopia and I've been happy with it. It allows me to have three Floppy
Drives instead of just two. I kept A: original and swapped B: for two half height TEAC 360K Floppy Drives.
That worked well for years. Now I'd like to add a GOTEK for C: until I get everything working correctly,
then swap the GOTEK to A:.

I'm still trying to update the GOTEK's, but keep having interruptions.

I too, would like to know more about the TurboROM and KayPlus from some other Kaypro users.


Larry
 
Advent TurboROM, MicroCornucopia or KayPlus?

Assuming I get one of the Kaypro 4/84s back to OEM spec I would like to then substitute one of these aftermarket ROMs to allow further modification of the system - mainly to augment drive capacity but also for the sake of greater utility. I have 27C64 EPROMs, an UV eraser and a GQ-4X programmer, as well as a source for the ROM code. I would have to create any support disks if I can find the source for them.

I'd like to hear anyone's opinions about which is easiest to implement, which has the best feature set, which is most bug-free, etc. Thank you for your replies.

-CH-

Because the original EPROM is only 4KB sized, do you use a modification (and if, what exactly) to get the 8KB into the socket ?
 
The socket is wired for both. You must register the 4K (24-pin) EPROMs at the bottom of the socket. I'm not sure about older Kaypro mainboards, but this one is setup for either size EPROM.
 
Because the original EPROM is only 4KB sized, do you use a modification (and if, what exactly) to get the 8KB into the socket ?

The OEM ROM, 81-292 for the 4/84, is a 24-pin PROM in a 28-pin socket. It is installed flush-right, with pin 1 to the left (as is the case with all other ICs on the board), as Durgadas311 was kind enough to point out when I asked in an earlier post.

This board is sometimes referred to as the "universal" board: Apparently Kaypro had plans for other machines and included options for expansion. In addition to the larger ROM socket there is a 50-pin header, J9, and three empty socket positions on the board, for example. My guess is they envisioned a 16-bit machine with a SCSI bus.

-CH-
 
FYI, the 50-pin header, J9, was used for the harddisk interface, and was a somewhat-generic I/O expander. It was not SASI/SCSI, though. It interfaced to a WD1002-series controller from Western Digital, and had a proprietary command structure. The Universal board was jumper-selectable for hi-cap floppies, and perhaps a few other customizations. I have not studied it, but there was a model that added an 8086 as a sort of co-processor - although I think that was a bit of a hack as I think you had to hijack the Z80 signals using a daughterboard. The last version of the technical manual has some information on a DOS machine as well.
 
It's my understanding that if you populate the missing components around that 50 pin connector, you can connect a FreHD disk emulator to it via an adapter board.

g.
 
FYI, the 50-pin header, J9, was used for the harddisk interface, and was a somewhat-generic I/O expander. It was not SASI/SCSI, though. It interfaced to a WD1002-series controller from Western Digital, and had a proprietary command structure. The Universal board was jumper-selectable for hi-cap floppies, and perhaps a few other customizations. I have not studied it, but there was a model that added an 8086 as a sort of co-processor - although I think that was a bit of a hack as I think you had to hijack the Z80 signals using a daughterboard. The last version of the technical manual has some information on a DOS machine as well.

The only WD1002 controllers I have found reference to are all designed to be inserted into a slot (ISA?) How was the WD connected to the J9 connector? And where would it have been stored in the case? Or was J9 THE connector? I mean, ribbon cable right to the drive?

-CH-
 
It was a stand-alone PCB with connectors. there must have been an interface board to convert between the Kaypro 50-pin "I/O expander" and the WD1002 40-pin interface. http://bitsavers.informatik.uni-stu...31050-0030_WD1002-05_HDO_OEM_Manual_Jul83.pdf It appears there were several variations of the WD1002, one was even SASI. This one was the one used for the Kaypro 10 (not SASI).

There are some photos out there, if you google Kaypro 10 you should find them. It bolted alongside the drive shroud. Here's a Kaypro 10 that used an earlier mainboard (not the "universal" one, this one was custom to the early Kaypro 10s). https://ancientelectronics.wordpress.com/tag/kaypro-10/
 
So I have 3 kaypro 4/84's and one 4/83. I want to add two frehd's to two of the 4/84's. Its my understanding that for full support and ease of use I can only use the kayplus rom. Is that correct?
 
I'm no expert on frehd or third-party Kaypro ROMs, but if the frehd emulates the WD1002-HDO controller, then you should be able to "convert" your 4/84 to a 10/10X using the IKaypro "Universal ROM" (81-478) - although that will restrict you to one floppy drive. I'm not sure if any of the ROMs support multiple floppy drives with the HDD - the hardware may not allow it: the "drive B:" select signal is also used as the HDD controller RESET signal.
 
I'm no expert on frehd or third-party Kaypro ROMs, but if the frehd emulates the WD1002-HDO controller, then you should be able to "convert" your 4/84 to a 10/10X using the IKaypro "Universal ROM" (81-478) - although that will restrict you to one floppy drive. I'm not sure if any of the ROMs support multiple floppy drives with the HDD - the hardware may not allow it: the "drive B:" select signal is also used as the HDD controller RESET signal.

Well that definitely is a problem as I need both floppy drives. The A drive is a gotek HXC emulator and the B drive is a conventional floppy drive.
 
This is what the Microcode Consulting web site (http://www.microcodeconsulting.com/z80/kayplus.htm) has to say about the KayPlus ROM:

"Written in Z-80 assembler for use under QP/M, CP/M 2.x and compatibles, features of KayPLUS include:

real-time clock for use with operating systems that support it such as QP/M
handles up to two hard drives of 64Mb each or combined total of 120Mb
partition any hard drive into multiple CP/M or QP/M drives
handles up to four floppy drives (may require additional hardware on earlier model Kaypro 10)
handles both 5.25" and 3.5" drives in a single package, including full motor control
intrinsic support for 13 different single-sided and double-sided 5.25" and 3.5" disk formats
access to over 120 disk formats via P2DSKDF utility
built-in logical-to-physical drive mapping
intrinsic support for Kaypro, Advent, or Emerald hard disk subsystems
increase Kaypro 10 disk utilization from 4476k to 5176k per drive
auto-detection of quad (96-tpi double-sided) drives
automatic boot of operating system when disk is present
resident monitor with eight commands including dumb terminal
automatic screen blanking after 15 minutes of screen & keyboard inactivity (Xerox 820-I only)
optional screen display of time
screen dump to printer with single keystroke
special ABORT and PAUSE keys (user-definable)
"
I don't have any experience with the KayPlus ROM but I intend to examine it more closely in the future.

-CH-
 
just to add the Bondwell-16 used the same HDD setup as the kaypro did they had a 34-50 pin driver board then that went to fdd and a wd1002 controller attached to the bottom of the st225 drive that then had the mfm cables go from the wd board to the drive as hdd1.IMG_20190219_164103.jpgIMG_20190219_164038.jpg
 
Note, not all WD1002's are created equal. The photo you show is a WD1002-SHD, which uses the SASI protocol. The Kaypro used the WD1002-05/HDO which is not software-compatible with the -SHD (is not SASI protocol). The controller hardware is also quite different.
 
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