Electronics America 8-Bit Single-Chip Microcontrollers User's Manual

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CHAPTER 9 8-BIT TIMER/EVENT COUNTERS 1 AND 2
(4) Port mode register 3 (PM3)
This register sets port 3 input/output in 1-bit units.
When using the P31/TO1 and P32/TO2 pins for timer output, set PM31, PM32, and output latches of P31 and
P32 to 0.
PM3 is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input sets PM3 to FFH.
Figure 9-7. Port Mode Register 3 Format
01234567Symbol
PM30
FF23H FFH R/W
Address After Reset R/W
PM31PM32PM33PM34PM35PM36PM37 PM3
PM3n P3n Pin Input/Output Mode Selection (n = 0 to 7)
0 Output mode (output buffer ON)
1 Input mode (output buffer OFF)