Talking of the 380Z...

Thay may have been used with external floppy units. The only way to be sure is to see what PCBs are inside. I was readign the 380Z service manual on vt100.net this morning. It was the first time I'd come across this board, it looks rather fun. I thought the 'full disk' controller was the 8" one (which was essentially the same as the normal 380Z controller), and that the one with the on-board Z80 was the Intellegent Disk Controller. But I could well be wrong. FWIW, the normal, non-intellegent disk controller has a SIO-4 on the same PCB, but it's nothing to do with the disk controller function. Obviously on that board you can go from serial port to disk without using the rest of the machine. I believe the SIO-4 board (also SIO-5, SIO-6) was just a disk controller board with the serial chips fitted and the disk controller chips not fitted. Much as the RAM expansion board is the same PCB as the CPU board, but you leave off the CPU and buffers, etc. That's what the service manual implied. I have a 480Z (one of the older metal-cased ones), but no disk unit for it. The keyboard interface spec is in the Information File and service manual. The latter also contains a scheamtic of _a_ keyboard, but from what I rmemeber the one I have is very different. Not that said schematic is a lot of use for making one, since the contents of the microcontroller firmware ROM are not know. The keyboard I have (and from what I remember we had at school) has a single 40 pin custom chip in it, nothing more. It would eb a fairly simple microcontroller project to make an interface No. What you need is the original (or known-to-be standard) cassette recorder. The point is that if the signal is inverted at any point, the system will not read high-speed (1200 baud) tapes reliably. I think it assumes a cycle starts with a rising edge, and if the signal is inverted, transistions between 1 and 0 bits on the tape and vice versa as seen by the system as odd-length cycles. This is explained (badly) in the information file. Years ago I made an RS232-CUTS tape interface unit. It suffered from much the same problem, I included switches to invert the record and replay phase. I found that you could _not_ depend on cheap cassette recorded getting the phase right, or even being consistent between record and replay. In other words, to load a 'standard' tape (in my case I used a commercially-produced BasicCode tape), you would have to invert the replay signal with some recorders and not others. And once you'd got that right, you would have to invert the record signal with some recorders and not others to get it to record a tape that would load with the same setting as the BasicCode tape. In the xase of the 380Z, what I want to do is to try to load a real RML tape, sort out the replay phase using that, then sort out the recording phase so I can load my own recordings. Oh well... -tony