Port Mode Register 3 Format - NEC PD78052 User Manual

(2) Port mode register 3 (PM3)
This register sets port 3 input/output in 1-bit units.
When using the P36/BUZ pin for buzzer output function, set PM36 and output latch of P36 to 0.
PM3 is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input sets PM3 to FFH.
7 6 5
Symbol
PM37 PM36 PM35 PM34
PM3
264
CHAPTER 13 BUZZER OUTPUT CONTROL CIRCUIT
Figure 13-3. Port Mode Register 3 Format
4 3 2 1 0
PM33 PM32 PM31 PM30
After
Address
Reset
FF23H FFH
PM3n P3n Pin Input/Output Mode Selection (n=0 to 7)
0 Output mode (output buffer ON)
1 Input mode (output buffer OFF)
R/W
R/W