TD2TIP.006 -- Making the TDD2 OS Work with Low Memory Programs
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With the TDD2, Tandy carried on its tradition of "unfriendliness" to
low RAM resident programs such as Supera and the PG Designs 0MENU
program.  The OS installed above 60000 by the loader is coded to load
BA programs at the bottom of RAM, pushing the low RAM resident
programs upwards -- where they are, at best, inoperative.

The original TDD OS (FLOPPY.CO on the menu) had the same feature.  A
fix was provided in TDDTIP.006.  Here is the same fix applied to the
new drive.

With the OS loaded above 60000 (MAXRAM = 60000), load and run the
following program:

10 POKE 62116,154:POKE 62117,249:POKE 62118,0
20 POKE60001,91
30 MENU

Line 10 makes the OS load BA programs to the top of the list (like the
cassette, and every other OS for the TDD/TDD2 that I know of).  Line
20 modifies the test value at 60001-60002 used by FLOPPY to test
program integrity -- since the computed value has been changed by the
patch.

You need do nothing more so long as the OS is resident.  But if you
reload it for any reason, rerun the patcher (I call it FIXFL2.BA)
before using the TDD2 with 0MENU or Supera.

Note that all other OS's I know of (e.g., TS-DOS v.3.0 for the TDD2)
do not need such a fix -- having been designed correctly in the first
place.

Phil Wheeler -- 71266,125
7/15/87