SIMH LGP-30 Progress.
billdeg at buzz1.com
Wed Feb 11 12:23:42 CST 2015
On Wed, 11 Feb 2015, B Degnan wrote:
> > via trial and error, and a lot of reading. I believe that loading the
> > bootstrap manually is a must; one cannot use or create tapes
> Only if your drum memory loses its contents. I don't know if SIMH has a
> concept of non-volatile main storage (drum, core). And for the LGP-30,
> registers are non-volatile, too.
When I fire up the SIMH and check 6300 we have
If the bootstrap came pre-loaded the first instruction of bootstrap should
be in 6300 and read
so, no unless the bootstrap is somewhere other than where I think it should
be, memory is completely blank when SIMH is loaded.
> > In order to enter instructions into memory I first learned how to
> > code from the various actual papertape sources, for example...
> > "flexowriter entry"> 6300 P 0000'
> > becomes
> > sim> d -a 6300 10000000
> Urks, that's sick... but SIMH should offer the possibility to enter the
> mnemonics and addresses (or anything else since everything is mapped to
> its four bit code) like
> sim> d -a 3w00 p0000 (or d -a 6300 p0000
sim> d -a 3w00 p0000
The SIMH *should* accept mnemonics ... Believe me I tried EVERYTHING ...
but unless there are hidden command switches you have to convert your code
to machine format. Scoured the entire C source code looking for clues.
> sim> g 3w00
g is not a legal command. You have to tell SIMH to execute with a "SET CPU
> Anyways, SIMH is not very well suited for machines like an LGP-30 where
> the user interaction with typewriter and console buttons for operation is
> imperative. The SIMH version does officially work, but it is not really
> user friendly in this case.
Tell me about it. I have written to the SIMH user group, so far I have not
received a reply with tips/testing done to verify "officially work"
> But the best would be if you use a drum image with 10.4 (the monitor)
> already loaded, i.e. save the memory contents to a file and reload it on
> the next incarnation of SIMH (there's a "START" drum containing 10.4 in
> simulator package, and an "ACT5" drum with preloaded ACT-V and
> subroutines, these may be usable in SIMH, but I don't know).
> > repertoire. The hardest part is finding ways to enter Flexowriter key
> > input via a modern keyboard, using SIMH commands.
> By using a simulator that offers the right frontend to the user (i.e.
> and buttons as required by the machine operations) *g*
Christian....I am going to keep at it and then script a bootstrap that will
load in SIMH, or convert tapes to SIMH format so they can be imported. I
can see why you did what you did with your simulator. Makes a lot of sense
to use function keys.
Here is the bootstrap I am working to complete. I need to find equivalents
to the Flexowriter commands, I have finished the memory insert commands,
please send suggestions if you have them.
sim> [first cpu fill c6300 in IR?]
sim> d -a 6300 10000000
sim> d -a 6301 01000000
sim> d -a 6302 11016305
sim> d -a 6303 10000000
sim> d -a 6304 01000000
here is where I need to experiment, the code below is my first attempt:
6309 (skip O.G.W.C flexo keys, still need to convert)
6326 000wwwwj (entered into by flexowr., need to convert)
6346 0gwc0000 (entered into by flexor, need to convert)
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