>
>
> > > > 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.
Absolutely. We are talking about the same thing. 'Coconut' was the HP code
name for the HP41C (and 'Halfnut' was the later model using the smaller
CPU board AFAIK).
> 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.
>
>
--
-tony
ard12_at_eng.cam.ac.uk
The gates in my computer are AND,OR and NOT, not Bill
Received on Thu Jun 26 1997 - 08:41:50 BST