Wayne, Warner, Glenn, Thank you very much for your responses!
Wayne, I took a look at the PDP11GUI files and it is quite complex. I setup the GUI on a PC here and tried it against my PDP-11/23 but wasn't able to get it to work. Not sure what I did wrong but I am definitely keeping it, and will go through that source a bit later. I'm sure I'll learn a lot from it. Thank you for the tip! Warner, Right now I prefer assembler because I am trying to learn more about it. But I glanced at the BSD loader in C and find it quite interesting. I am going to go though that too a bit later. Thank you for this tip as well! Glen, I did look at the sources you mentioned and they were a bit more bite-sized. So I have tinkered with it and am actually able to use it to boot an 11/23 in SIMH using that code. I have also cobbled together a little boot menu and incorporated this loader there. Thank you for those pointers! Thank you all! -Peter On Tue, Oct 28, 2025 at 6:38 AM Glen Slick via cctalk <[email protected]> wrote: > (DU) MSCP UDA50(RAxx) disk: > > https://ak6dn.github.io/PDP-11/M9312/ > > https://ak6dn.github.io/PDP-11/M9312/23-767A9/23-767A9.mac > > https://ak6dn.github.io/PDP-11/M9312/23-767A9/23-767A9.lst > > > > On Mon, Oct 27, 2025, 4:48 PM Wayne S via cctalk <[email protected]> > wrote: > > > Maybe look at pdp11gui ? > > I think it downloads a boot loader so the code may be there. > > <https://retrocmp.com/tools/pdp11gui> > > PDP11GUI<https://retrocmp.com/tools/pdp11gui> > > retrocmp.com<https://retrocmp.com/tools/pdp11gui> > > [favicon.ico]<https://retrocmp.com/tools/pdp11gui> > > > > > > > > Sent from my iPhone > > > > On Oct 27, 2025, at 15:58, Peter Ekstrom via cctalk < > [email protected]> > > wrote: > > > > I am looking for the assembler listing for a bootloader for booting from > > MSCP disks like RD-disks. > > Google has not been very helpful and my assembler knowledge is not enough > > for me to write one from scratch. Does anyone have one they can share? > > > > - Peter > > >
