Hello.
Before a few weeks, i bought Kaypro II (not 2), the first version. Normally, it has 2 Tandon single sided double density floppy drives. But this one had 2 Shugarts SA465 double sided quad density drives. Of course, it works not in QD mode.
But there is a mod. They soldered cable from Z80 PIO to a logic chip and from logic chip to side select line on pcb floppy cable plug. So, original bootdisk, made with teledisk on ibm 5170, did not work. I checked with logic probe. Side 0 is logic high, side 1 is logic low. After start is first high, then is switches to low to get access to the side 1. I removed the boot eprom an checked the dump. The dump isn´t original. So, i cutted the cable to drive select line and wrote another eprom with original dump. Kaypro starts from bootdisk and works fine in single sided mode.
But of course, i am interestet to get running the computer with double sided bootdisk. I tried different versions from newer Kaypro 2. Not working. Perhaps, anybody knows this mod ? I have seen the same cable connections in a youtube video. But i cannot find this video anymore, otherwise i would ask on youtube.
Perhaps anybody can take a look to the dump !?
View attachment BIOS_U47_bought with custom dump.zip
It would be nice to know, which diskettes i can use with this dump...
THX !!
Jan
Before a few weeks, i bought Kaypro II (not 2), the first version. Normally, it has 2 Tandon single sided double density floppy drives. But this one had 2 Shugarts SA465 double sided quad density drives. Of course, it works not in QD mode.
But there is a mod. They soldered cable from Z80 PIO to a logic chip and from logic chip to side select line on pcb floppy cable plug. So, original bootdisk, made with teledisk on ibm 5170, did not work. I checked with logic probe. Side 0 is logic high, side 1 is logic low. After start is first high, then is switches to low to get access to the side 1. I removed the boot eprom an checked the dump. The dump isn´t original. So, i cutted the cable to drive select line and wrote another eprom with original dump. Kaypro starts from bootdisk and works fine in single sided mode.
But of course, i am interestet to get running the computer with double sided bootdisk. I tried different versions from newer Kaypro 2. Not working. Perhaps, anybody knows this mod ? I have seen the same cable connections in a youtube video. But i cannot find this video anymore, otherwise i would ask on youtube.
Perhaps anybody can take a look to the dump !?
View attachment BIOS_U47_bought with custom dump.zip
It would be nice to know, which diskettes i can use with this dump...
THX !!
Jan