On Aug 21, 2015 10:21 PM, "Ali" <cct...@fahimi.net> wrote: > > One question: from the pictures it was not clear if this used the three or two connector Pertec interface? I am guessing two but better to ask than end up with a 200lb paper weight! > > -Ali
A Fujitsu M2444AC should have two 50-pin connectors for a formatted Pertec interface. The 'C' suffix of that model number means that it is cached. The manual probably explains the details of how that works. I think it is basically a read ahead buffer during read options so if the host can't read data fast enough to keep up with the tape movement the drive can keep moving and reading into the cache until it fills up. That can eliminate a lot of back and forth tape repositioning with slow hosts. I had some Qualstar 1052 tabletop drives which were not cached. When used with a PCTD-16 ISA bus interface controller in a PC they weren't too bad since the PCTD-16 has its own on board buffer in the 256KB - 1024KB range. When used with a Q-bus Pertec interface in a PDP-11 they were a lot slower since neither the controller nor the drive had any real buffer space to help keep the tape moving. Much slower than the same system with the cached M2444AC instead.
