HP-21MX bootstrapping?

Tim Riker Tim at Rikers.org
Sun Feb 17 16:32:52 CST 2008

ok, been meaning to actually run something more than the little assembly 
   test apps on my HPs. How do folks bootstrap systems?

I've got 2 working HPs (HP-2108A and HP-2112A) and HS-TERMINAL (ie 
HP-12531B) and I can get lights to light up with a 2400 baud connection 
and this snippit running:

0001* set to TTY I/O number
0002  00011         SC    EQU 11B

0004  00040               ORG 40B
0005  00040 106700  LOOP  CLC 0        Turn off I/O interrupt system
0006  00041 060051        LDA TTYIO    Load A-register with control word
0007  00042 102611        OTA SC       Output control word
0008  00043 103711        STC SC,C     Set control, clear flag
0009  00044 102311  WAIT  SFS SC       Wait for flag
0010  00045 024044        JMP WAIT     Loop till ready
0011  00046 106511        LIB SC       Input data word
0012  00047 106601        OTB 1        Output data word to switch register
0013  00050 024040        JMP LOOP     Next char
0014  00051 160000  TTYIO OCT 160000   TTY input and print control word
  LOOP 000040   01/0005 -- 01/0013
    SC 000011   01/0002 -- 01/0007 01/0008 01/0009 01/0011
TTYIO 000051   01/0014 -- 01/0006
  WAIT 000044   01/0009 -- 01/0010
4 symbols
14 lines assembled, 10 words generated
0 errors, 0 warnings

(also online as http://rikers.org/hp2100/ttyin.lst)

so what's next? Is there a tape loader for use over a 12531?

Also, I'm using a modified version of the perl assembler. I'd like to 
actually use the native HP assembler under SIMH. The HP / CHM agreement 
should allow for at least this much bootstrap information to be shared. 
I'm happy to put up bootstrap instructions and tape images if someone 
can provide them.

I don't have any other peripherals tested out yet. Not sure why my real 
paper tape reader is not working yet. My paper tape punch is a long ways 
from working and it's not HP equipment anyway.

I've got tape images that work in SIMH like the HP-Basic. Just want to 
see these work on real hardware by loading them over a serial line.

There are quite a few HP collectors out there. How do you folks boot up 
your hardware? ok, I could get an HP-7970 9 track, but I don't have that 
either. It would seem useful to be able to bootstrap any given tape over 
serial. I know it's only 2400 baud, but just about every HP collector 
should have the needed hardware. :)

Help me out!

PS: Some nice list owner promised to get me a CD full of stuff to get 
started, but alas, I'm afraid my process is never getting scheduled. 
Perhaps I need more of a real-time OS.
Tim Riker - http://Rikers.org/ - TimR at Debian.org
Embedded Linux Technologist - http://eLinux.org/
BZFlag maintainer - http://BZFlag.org/ - for fun!

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