hmb's latest activity

You mean like this "virtual sector generator" for 5.25" floppy drives ? https://deramp.com/vsg.html

For proper operation, the old school QumeTrak 842 does require a "TG43" input signal. In the Qume manual the "TG43" signal is actually...

While the joystick mechanism used by the Cromemco controller is mechanically similar to that found in Kraft's RC transmitters, I wonder...

86-DOS would work with a very basic serial terminal. When used with a VT-52, its function keys could be used to perform several very...

The system console was a serial terminal connected to the serial port on the SCP-300 "CPU Support Card".

The only way to find out for sure is to test it so that you can verify this claim by the manufacturer was correct. Your Delta Products...

Each of these two external drive systems required a specific H89 interface board. Needless to say these interface boards (like the Z-47...

Few H8 (or H89) systems were equipped with 8" floppy drives. The "official" Heathkit 8" drive product for the H8 was the H-47, a very...

No question - the CompuPro RAM17. It's design (like the SCP 16K board) uses the least number of parts, and S100 signals, required for an...

In Holden's discussion of the Dazzler, he mentioned having successfully tested it with the "Seattle Computer" 16K RAM board, and the...

The only board in your list that stands a chance of working with the Dazzler is the Vector Graphic 8K RAM - but I'd have to see the...

As you pointed out for the Memory Merchant 65K16S board, the S100 address signals A0-A15 are latched by 74LS375s. The 74LS375 is a...

Correct. R1 is 270 ohms on both RevC and RevD boards. There is a typo in post 340 - the reference to "R1 should be 30K" should have...

I found an older (1980) version of the Cromix manual which only describes use of the 64KZ and no other RAM boards - which matches your...

I just quoted what the Z80 Cromix Admin Manual said. Perhaps it was a later version published after the original 64KZ had been...