I have a TD Systems Viking QTO MSCP emulating SCSI tape QBUS controller and I found a manual for that one one the net: http://manx.classiccmp.org/collections/antonio/chrisq/TD_Systems_Inc_-_900-… But I rather have a disk controller rather than a tape controller. Or a combined tape and disk. An old post from '99 ( https://groups.google.com/forum/#!topic/alt.sys.pdp11/2XddHq03SQI) indicate that the web address is www.tdsys.com. Accessing this webpage just informs me that the company doesn't exist any more. But someone is paying the domain fee. I tried to email but hasn't got neither a bounce nor a reply yet. I would guess that it is all up to the EPROM and the PAL chip to decide how this card is working. QDO, QTO, QDT, QDD or QDA. The PAL is a simple 16L8 so it is most certainly only used for address decoding and should be pretty simply to change. The EPROM contents is a problem though. I dumped it and did some initial checking with a Z80 disassembler and simple operations like "strings". There are a lot of strings in there. Some of them seems to relate to tape drives, like "EXABYTE", "WANGTEK" and "space forward". But also others that seems to be disk oriented like "Booting from DU0", "Disk common command set" and "Fomat unit". A couple of years ago a someone sold such a controller on Ebay but also included an EPROM and a PAL to convert it. I contacted this seller but never go a reply. Does anyone have this controller? Know anything about it? Has anyone converted it from tape to disk?