Arfon Gryffydd <arfonrg(a)texas.net> wrote: OK, if you go to http://oscar.taurus.com/~jeff/2100/emulator/index.html ...you will find the sources for the simulator and some other bits. e21.c is the simulator core. ttyaccess.c is a file lifted from Doug Jones' PDP-8 simulator. They get compiled and linked together to make the simulator, e21. hpasm.c is source for an HP21xx cross-assembler. I haven't done anything with this. chkasm.c is source for a program that checks an HP21xx absolute binary tape to make sure it is OK with its checksums. I haven't done anything with this either. Turns out Jeff did most of his development work under MS-DOS, and I think it probably works best there. I don't know what C compiler he used for MS-DOS. For Un*x, there is the file mkunix which contains commands to compile this stuff. It's not exactly a shell script but may be used as standard input to a shell. Building e21 under FreeBSD requires that you remove -DTERMIOS, and you will then notice that the simulator's prompts are wacky because it puts the tty patches that make it switch the tty back and forth as needed but they introduce another bug, namely the simulator exits when the simulated 21xx halts. Oops. OK, so now supposing you've got it built, go get something else: http://oscar.taurus.com/~jeff/2100/hpbasic/basic1.abs That's an absolute paper tape image for a single-user standalone BASIC interpreter that will work with the simulator. Now run e21, tell it to LOAD basic1.abs, and then to RUN. Case is important for the simulator's commands. That should get you running the standalone BASIC. Fun, huh? When you get tired of this, type BYE to the BASIC interpreter, and it should drop you back to the simulator's U2100> command prompt. Q will exit the simulator. -Frank McConnell