abbiel@ucscb.UCSC.EDU (03/29/90)
Hello Everyone! I am new to reading handhelds and think it's great. The HP48
is a very exciting machine we'll have to agree. I wonder why nobody has made
mention yet of of the following possibility. Wouldn't it be possible to make
the PC a terminal for the '48? In other words could we use our nice editors
and keyboards and yet be _within_ the HP's interactive environment? This
might solve alot of the problems that are being addressed here with emulators
for example. On the PC end one would need a TSR (or equiv.) to run on top of
their favorite editor.
The TSR would have the intellegence to parse the output in such a manner that
it holds characters until it recognizes a valid HP command or receives a
special 'ENTER' key sequence and then echos the string out the com port. It
would also receive the '48 output and display it in a status window on the
screen. It would also need to do some character translation, for example to
and from extended ASCII. Of course, someday it could be even extended to
handle graphics, although that would be very challenging.
This approach would minimize the work on the other end where things get a
little sticky. The '48 would have to receive the string, 'EVAL' it and echo
the display out the wire. In a fairly small program it might even be possible
to mimic some of the HP's status/menu lines.
I picture this as an ideal development environment for the HP. Both machines
would be side-by-side and both keyboards and screens would be active! Anything
short of that would also be a significant improvement. For example how about
just a TSR that clips a box of text out of your editor and kermits it to the
'48 with a little character translation. I don't have time to work on this
now but any comments or suggestions would be appreciated.
On a different note:
I noticed that 'TAG'ed objects loose their tags when 'EVAL'd (or 'STO'd) and
wrote the following snippet of code which may prove useful (until somebody else
comes up with a more clever approach). It is a replacement for 'STO' and
takes the same inputs. It will store any object in the following format:
<< :NAME: OBJECT >>
Which will 'EVAL' to a tagged object automatically when it is used. My
version also 'DISP'lays what has been stored which makes a great program status
indicator for some of my lengthier code. To eliminate this feature remove the
commands DUP 3 DISP. One disadvantage to this approach is that vars take up
an extra 8 bytes in this format.
HP48SX CODE
%%HP: T(3)A(D)F(.);
\<< DUP ROT ROT \->TAG
DUP 3 DISP \->STR "\<<"
SWAP + "\>>" + OBJ\->
SWAP STO
\>>
I also want to mention my experience on the RS-232 cable. It works great! On
the 9 pin D on my 'AT clone pin 5 was GND (not 7). Also, Molex makes a 2mm
connector system that plugs onto the '48 well. It is called the 51004 housing
and 50011 crimp terminal "Wire To Board System." Wires may be soldered to the
terminals if the special crimper is not available.
Best Regards to all and thank's for all the great work!!! Larry L. Hoppis