using a DRV11 to run an IDE drive?

Yes, it is possible to connect a DRV11 to an IDE disk drive. However, you must compromise. I connected a IDE disk drive to some simple parallel ports of the I/O Board. But it is PIO mode only, no DMA, so not really fast but it works. The lowest level software is fairly easy. Check www.pdp-11.nl and click on the link "Home-brew PDP-8". You can download the 6809 source code which even resembles (a little) PDP-11 mnemonics. I thought to get it working with 8 bits, but it is a lot easier if you have a 16-bit data path. That means 16 inport bits and 16 outport bits. Further you need a few (6?) extra output lines for control. So perhaps one DRV11 is just not sufficient, but I would say: yes, you can connect an IDE drive to one (or two) DRV11's. BTW, if an IDE hard disk works, I found out that a Compact Flash Card with IDE adapter works just fine too. Solid state disk on your PDP-11! - Henk, PA8PDP. -----Original Message----- From: cctalk-bounces at classiccmp.org To: General Discussion: On-Topic and Off-Topic Posts Sent: 30-3-2005 20:18 Subject: using a DRV11 to run an IDE drive? I've seen an old PC trick that uses the printer port and custom cable to bit-bash interface an IDE hard drive or cdrom using a dos .sys driver. Anyone think it's possible to do the same with a DRV-11 for the pdp11? Features: built in BAR/WCR/CSR circuits, 16 bits in, 16 out. 6 function bits, Attention/Ready/Cycle Request/Bust handshake bits etc Perhaps a small pld or fpga could use the spare handshake or function bits to latch the 3 address bits for the IDE and generate the chip select/read-write etc while the 16 bit input and output busses could be joined via tri-state buffers... I'ts not a replacement for a scsi controller, but it beats hunting down the hard to find bus interface chips and provides a proven already working basic interface. I've got a dozen of the QBUS (and a few UNIBUS) DRx11 boards if someone is interested in fooling with the idea. As a side note - I recall UW's CCNG CE dept fashioned an early MP cluster called using DRV11s to connect LSI11-2s in the 80's. regards -h