(PC-1211) Engineering format

[robve]

(05-13-2022 05:43 PM)robve Wrote:  [...]
So all that we need to do to create a new "MERGEd" program is manipulate these pointers and POKE a small new program in memory with this 3 liner:

Code:

1 "NEW" L=PEEK 65497,H=PEEK 65498,E=L+256*H: POKE 65499,L,H: POKE 32779,L,H
2 POKE E,255,0,1,5,34,42,42,34,13,255: E=E+9,H=INT(E/256),L=E-256*H
3 POKE 65497,L,H: POKE 32777,L,H: END

To create a new "MERGEd" program:

• RUN "NEW
• then edit the label "**" at line 1 to define a new label for the program of your liking
  

To delete the last program MERGEd:

• DELETE 1,
• WARNING: DELETE has a bug that deletes the last program that was RUN or edited, instead of the last program merged. To avoid this, delete one line of the program first, then execute DELETE 1,
  

After a bit of experimentation with the PC-1350/60, I found that LIST may show incomplete listings after running "NEW". The programs are still there, but aren't always LISTed, unless you use LIST "label" and everything looks OK again. Deleting the last program shows nothing with LIST afterwards. Again, the programs are still there and are perfectly RUNnable. Deleting the last program does not seem to be a good idea since things may get unstable as I had noted.

Apparently, there is an internal flag in RAM to indicate merged programs are present, because the problem does not happen after executing a normal MERGE, which presumably sets this flag. It's not a big problem to use the "NEW" program, just don't delete the last program. To work around this, before using the "NEW" program, it might be best to CLOAD/LOAD a program (like the "NEW" program), then MERGE another program to activate this state properly. This way the LIST and delete problem never happens on the PC-1350 and PC-1360 and the "NEW" program creates new program slots without issues. Now, if I could just find the location of this darn flag in RAM to activate. Also still need to finish the MERGEd program rotator in assembly.

- Rob