On Jun 1, 2017 12:51 AM, "Glen Slick via cctech" <cctech at classiccmp.org> wrote: mounted with simh? I have a couple of dozen I would like transferred because I am downsizing. <snip> I have a PDP 11/40 with twin rl02's. I send the data through serial card into Win XP laptop running PDPGUI and use the built-in disk image utility. Slow but reliable. Bill

sorry I see "couple dozen" On Wed, May 31, 2017 at 1:56 PM, william degnan <billdegnan at gmail.com> wrote:

On Thu, Jun 1, 2017 at 7:59 AM, Jay Jaeger via cctalk <cctalk at classiccmp.org> wrote: Interesting. I'd like to see how you tackled that (I can imagine wanting a couple of layers of integrity-checking, for one). Neat. Any write-up of this or shared code to keep from re-inventing the wheel? I was going to do a bunch of imaging with a basic machine and vtserver, but this sounds much, much faster. I have piles of 8" floppies, RK05 packs and RL02 packs to copy off. Not doing it at 1KB/sec is always an option. -ethan

On 6/1/2017 12:12 PM, Ethan Dicks wrote: It uses a simple 8 but parallel bus-like fully interlocked protocol, byte by byte. The send side raises a data available bit, the receiver grabs it, then raises an acknowledge. The sender then drops the available, and then waits until the receiver drops the acknowledge. The cable is less than 6 feet, and isn't even using properly twisted pairs. Transfers are 512 byte blocks (one can always pad the last block with something), and each block starts with a "sync" byte, which prevents losing (or adding) an entire byte - the protocol will lock up - there is no recovery. And I have never needed any. I have yet to see a transfer fail once it gets started. Sometimes one does need to restart one end or the other to get it going - I never bothered to look real hard at why that happens. One can check the integrity of the entire image however one chooses. I use a simple 16 bit CRC (sum -r), and wrote a MACRO program under RT-11 that will do the same for a file or a device. Here again, I have never had a bad checksum. It just works. Note that while transferring FROM a device that supports bad blocks (e.g., RL01) is the same as any other device (with or without the bad block table), one needs to be careful about transferring TO such a device to make sure that one does not overwrite the factory bad block table. Well the above was an error on my part. I should have written "old *parallel* port. I could do something about writing it up, I suppose, but it really is pretty straight-forward. A couple of PDP-11 MACRO programs, running under RT-11. (The PC parallel port code was done in DeSmet C, originally on a Netronics 8088 based true IBM PC "clone", now running under Windows 95, and does not work with modern parallel ports, rendering it kind of useless.) A couple of Arduino programs (I hate the term "sketches") that talk the PDP-11. A couple of perl programs that talk to the Arduino (which uses an Ethernet shield). And NONE of the code is up to snuff, by my standards. In just about every case, I have had a short term goal to accomplish, and stopped once that was working well enough. Things like: - The PDP-11 halts before RT-11 can send out a full error message (it really should loop on an error). - Errors don't provide any data about what the program didn't like - No time spent cleaning up code (in fact, this weekend I spotted a coding error on the Arduino program that reads from the PDP-11, that fortunately doesn't seem to have had any really bad effects). - etc. Jay I played with VTServer as well. This is indeed much faster than a serial port - and the Arduino version is a bit faster than the old PC version. I have used it for all of the media you mention, and for RX02 floppies and RK07 packs as well, though these days I normally transfer floppy images to the PC using a Catweasel bit cell board.

My setup is an 11/70 running BSD 2.11. I ?dd? the RL pack to a file on one of the file systems (I have the equivalent of 4 RP06 drives) and then ftp it to where I want it (since the 11/70 is on my network?actually at one point it was on the internet where anybody could log-in). I can also do that with RK05?s and RX02?s. ;-) TTFN - Guy