Subject: Re: Simulated disk drive for RT-11? From: "Jerome H. Fine" <jhfinexgs2 at compsys.to> Date: Mon, 06 Jun 2005 19:25:41 -0400 To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org> Jerome Fine replies: RT-11 can boot any device which looks like a disk drive - for which there is also the boot code in the device driver. Thus far I am not aware of any such devices that do not have the needed boot code, including the DD(X).SYS device driver for the TU-58. There is, of course, ONE exception - the LD(X).SYS device driver which is DEC's answer in RT-11 for sub-directories. If you first want to become experienced with RT-11 without all the hardware problems, then there are several V05.03 RT-11 distributions available. One of those distributions also includes all of the prior RT-11 distributions. The file, RT11DV10.ISO.zip is at: http://www.classiccmp.org/PDP-11/RT-11/dists/ Note that you can actually boot the CD that can be burned from RT11DV10.ISO (after you UnZip the file). Or if you run SIMH, you can: ATTACH RQ0: RT11DV10.ISO SET RQ0: LOCK BOOT RQ0: to run V05.03 of RT-11. Of course, you can also legally run under E11 if you purchase an RT-11 license from Mentec for about $ US 900 (the latest price I have heard) and perhaps the distribution kit for $ US 1600 (also the latest I have heard). For hobby use, there is no charge for the hobby use of E11. The E11 commands are: MOUNT DU0: RT11DV10.ISO/RONLY BOOT DU0: If you can use some help with running RT-11, please ask If you really want to run on real DEC hardware, then you obviously need some sort of disk drive as well. Even a TU-58 needs additional space and the 4 * 4 backplane is just too small to be really useful.

The BA23 box is probably a much better solution since there is also space for 2 * 5 1/4" drives and the power to run them. An M7555 RQDX3 and an RX50 floppy is probably two orders of magnitude better than a TU-58. A hard disk drive might be a bit more difficult, although an old ST412 at 10 MBytes looks like (actually is) an RD51.