TI 58/59 ROM modules and OP instructions

[Gene]

I don't suspect it is related to the OP instructions in CROMs.

User ram programs converted a regular number in the display to an internal numeric format (an NNN?) before executing each program instruction and then BACK to the regular numeric display. Very time consuming.

CROMs did not do this as they were not normally interruptible by R/S while running...as I recall.