rwh@aesat.UUCP (Russ Herman) (01/15/85)
I want to modify the September 1984 Compute Gazette SpeedScript
custom boot program. The tail end of it looks like
160 print"[CLEAR]pO43,1:pO44,"hs"
162 print"[DOWN][DOWN]p045,",le":pO46,"he"
164 print"[DOWN][DOWN]save"chr$(34)nf$chr$(34)","dn
166 data19,13,13,13,33,131
168 poke198,6:fori=631to636:readn:pokei,n:next
The accompanying text contains
"Lines 160-168 print the statements to perform the POKEs and to
save and run the new SpeedScript; they also fill the keyboard
buffer with a HOME character, three RETURNs, an exclamation
point, and the code for LOAD and RUN."
Generally I understand the techniques being used. It's a clever technique for
loading a program in high core that loads an ML program, modifies it, and
then executes it after diddling back the BASIC pointers via screen memory and
the keyboard buffer. What I *don't* understand is the last two
characters stuffed in the keyboard buffer. What is the significance
of an exclamation point? The only reference I can find to code 131 is its
tabling in the Transactor reference issue as "LOAD and RUN" - how is it used?
Other references show 131 as the token for DATA - nothing to do with load/run.
What I am intending to do is simply RUN the patched version of SpeedScript
without saving and reloading it: I assume I can replace the "save" command
with a "run" command and delete the 131 and maybe the 33 (changing the count
accordingly). Sound reasonable? Please e-mail if you can explain, as I doubt
if this is of general interest.
--
______ Russ Herman
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