> > SIMH has never directly supported mounting/attaching virtual TU58 devices. > Altho the required serial interface > is emulated (ie, a plain DL11 at 776500/300) the TU58 drive behind the > serial interface has never been emulated. > > > I just tested the latest SimH from github and it is indeed possible to enable tdc and attach an image file to the tdc0 device. I then booted into RT11 from a DU-device and did INIT DD0: no problem. Then I made a bootable DD image. I did even do a BOOT DD0: which gave me a RT11-prompt. But booting from SimH failed on me. I am not sure why.
MattisMacBook:BIN mattis$ ./pdp11 PDP-11 simulator V4.0-0 Beta git commit id: 1b6f28a7 sim> set tdc enable sim> attach tdc0 rt11-dd.dsk TDC: creating new file TDC: buffering file in memory sim> attach rq0 rt11v53-games.dsk sim> b rq0 RT-11SJ V05.03 .init dd0: DD0:/Initialize; Are you sure? Y .copy dd.sys dd0: Files copied: DK:DD.SYS to DD0:DD.SYS **** Copying some files ***** .copy rt11sj.sys dd0: Files copied: DK:RT11SJ.SYS to DD0:RT11SJ.SYS .copy/boot rt11sj.sys dd0: .boot dd0: RT-11SJ V05.03 .dir DD .SYS 5P 20-Dec-85 TT .SYS 2P 20-Dec-85 SWAP .SYS 27P 20-Dec-85 STARTS.COM 1P 20-Dec-85 DIR .SAV 19P 20-Dec-85 DUP .SAV 47P 20-Dec-85 DU .SYS 8P 20-Dec-85 RT11SJ.SYS 79P 20-Dec-85 8 Files, 188 Blocks 316 Free blocks .boot du0: RT-11SJ V05.03 . Simulation stopped, PC: 146414 (BCC 146446) sim> exit Goodbye TDC: writing buffer to file PDP-11 simulator V4.0-0 Beta git commit id: 1b6f28a7 sim> set tdc enable sim> attach tdc0 rt11-dd.dsk TDC: buffering file in memory sim> b tdc0 Trap stack push abort, PC: 000000 (WAIT) sim> I have no idea why SimH is not able to boot from the simulated DD0: device. The steps to make a bootable dd0: was exactly the same steps as to make a bootable RK0: which works just fine. Ersatz-11 on the other hand works fine with the same image: E11>assign tt1: dda: E11>mount dda0: rt11v53_dd.dsk E11>b tt1: RT-11SJ V05.03 .dir TT .SYS 2P 20-Dec-85 DD .SYS 5P 20-Dec-85 RT11SJ.SYS 79P 20-Dec-85 SWAP .SYS 27P 20-Dec-85 STARTS.COM 1P 20-Dec-85 DIR .SAV 19P 20-Dec-85 RESORC.SAV 25P 20-Dec-85 7 Files, 158 Blocks 346 Free blocks . This is the image that boots in Ersatz-11 but not in SimH: https://dl.dropboxusercontent.com/u/96935524/rt11v53_dd.dsk.gz Since it boots on Ersatz-11 when set to 11/03 CPU it should work on the real hardware. BTW. It not so that the LTC interrupt is enabled in your system? I have had problem with that one. In certain cases it need to be disabled. If I remember correctly I had problems booting RT11 from MSCP devices with LTC enabled. /Mattis > Don >