Chris G. wrote: >This reminds me of something I wanted to ask for some time:
>I've got a Tektronix 8560 where the internal hard disk is not that much >reliable anymore. No read/write errors, but after running for >some time (btw. >24h and 48h) it seems to reset. >Spin-down, spin-up, etc. until the host receives an error. >The connector for an external hard disk looks like an external SCSI connector. >I haven't found the pinout or other description in the >docs. My hope was that >it might be really SASI or SCSI, but given the release date of the machine (I >don't know exactly but I think >around 1978 or 1979), it might not be. >Does anyone know more details about this connector/connection? If I recall correctly, these machines used an 8" Micropolis hard disk drive. These were most definitely not SCSI, or even SASI. They used a proprietary Micropolis parallel interface. The disk expansion connector, while looking like it might be a SASI/SCSI connector, isn't...it brings out that Micropolis interface. Many, many moons ago, when I worked at Tektronix, I purchased a number of these drives (I think that they had a capacity of 35MB , IIRC) at the Tektronix Country Store (they were cheap), and built an interface for a Tektronix Board Bucket (6809 CPU) so I could use the drives on the system. It wasn't a difficult interface (it was TTL, if I remember right) to write code to talk to, and I was able write a driver for it for the FLEX operating system. I wouldn't try plugging anything into that external connector, unless it's an original Tektronix disk expansion unit for the 8560. Of course, as mentioned, this is all IIRC (If I Recall Correctly). -Rick -- Rick Bensene The Old Calculator Museum http://oldcalculatormuseum.com