25 Jun
1997
25 Jun
'97
9:28 a.m.
> > Remember it? If it's what I am thinking
of, I was doing it a couple
of
> > weeks ago. You are talking about a
'Coconut', right (explanation of
that
> > codename also on request - it has _nothing_
to do with the Tandy
CoCo).
> > Nowadays I do something similar. I create a
GROB with the right bit
> > patterns, use the SystemRPL 'Get' routine to remove the header, and
thus
> > create new objects.
No, not quite. The HP-41C used 2, 3 or 4 bytes to create the program steps.
By forcing apart the bytes and substituting new ones, new ("synthetic")
opcodes could be created.
These ranged from creating new characters to being able to access areas of
memory.
Ah, the heady days of discovery! Mother HP wouldn't officially help, but
there was plenty of behind-the-scenes help.
26 Jun
26 Jun
1:41 a.m.
> > Remember it? If it's what I am
thinking of, I was doing it a couple
of
> > weeks ago. You are talking about a
'Coconut', right (explanation of
that
> > codename also on request - it has
_nothing_ to do with the Tandy
CoCo).
> > Nowadays I do something similar. I
create a GROB with the right bit
> > patterns, use the SystemRPL 'Get' routine to remove the header, and
thus
> > create new objects.
No, not quite. The HP-41C used 2, 3 or 4 bytes to create the program steps. By forcing apart the bytes and substituting new ones,
new ("synthetic")
opcodes could be created.
The famous 'byte grabber'....
These ranged from creating new characters to being
able to access areas of
memory.
Ah, the heady days of discovery! Mother HP wouldn't officially help, but
there was plenty of behind-the-scenes help.
Of course if you were a real hacker you had an M-code box that let you
write the native 10 bit (?) instructions for the 41's CPU (I forget what
it's called).
The trick with a Grob is a 48 series trick for creating objects (code
objects, systemRPL prgrams, Arrays of things other than real/complex, etc)
directly on the machine without needing any other software or a PC to
download them from. It's the logical replacement of synthetic programming
on the more recent machines.
10041
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