New find, Heathkit H89 computer.

Hi Bob As for being in your area, I was think you were Bob Rosenbloom :( Still, it sounds like you do have a softsectored machine if it only has one hole. Has this disk been confirmed to boot the machine or is it just a disk that someone said booted the machine? There were soft sectored cards but these were uncommon. The hard sectored drives used a USRT on the controller card. The soft sectored used a regular disk controller. The ones in the H8's used a Z80 but I don't think this was the way it was done on the H89. I've been looking for a softsectored card but not found one. 360K media comes up all the time on Ebay. I've seen boxes of over 100, new, go for around 10 cents each. If you have a PC that can run DOS and can mount a 360K disk drive, you should be able to transfer soft sectored images using one of the disk tools out there. The SEBHC has some soft sectored suff in its library but I'm not sure of the format or tool used. As for CP/M, the machine needed a special logic array chip to do true CP/M. This is because it had a boot ROM at address zero. There is information on this logic chip someplace on the web but I don't recall where. There was a version that didn't boot at the normal address but I've never heard of anyone using it. Several people in the SEBHC group run CP/M on their machines. I believe this is both soft and hard sectored. Also, the machine normally came with 48K. In order to get to the full 64K, there was an add-on card that plugged into the expansion bus but needed an additional wire between the card and mother board to get the full 64K. You should subscribe to SEBHC and ask there. There are a couple people on that group that were involved in the original H89 hardware and software. I only run HDOS applications on my machine and I've not tried to convert it for CP/M. I have an IMSAI with CP/M 2.2 on it and that is generally sufficient ( except of course, CP/M 8000 on my Olivetti M20 ). Dwight