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CHAPTER 7 8-BIT TIMER/EVENT COUNTERS 50 AND 51
User’s Manual U19780EJ2V0UD
249
(3) Port mode registers 1 and 3 (PM1, PM3)
These registers set port 1 and 3 input/output in 1-bit units.
PM1 and PM3 can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation sets these registers to FFH.
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78K0/KB2-A
When using the P11/TI50/TO50/RxD6 and P10/TI51/TO51/TxD6 pins for timer output, set PM11, PM10 and
the output latches of P11, P10 to 0.
When using the P11/TO50/TI50/RxD6, P10/TO51/TI51/TxD6 pins for timer input, set PM11 and PM10 to 1.
At this time, the output latches of P11 and P10 may be 0 or 1.
Figure 7-9. Format of Port Mode Register 1 (PM1)
Address: FF21H After reset: FFH R/W
Symbol
7 6 5 4 3 2 1 0
PM1 1 1 1 1
PM13
PM12
PM11
PM10
PM1n
P1n pin I/O mode selection (n = 0 to 3)
0
Output mode (output buffer on)
1
Input mode (output buffer off)
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78K0/KC2-A
When using the P34/TO50/TI50/INTP2 and P33/TO51/TI51/INTP3 pins for timer output, set PM34, PM33
and the output latches of P34, P33 to 0.
When using the P34/TO50/TI50/INTP2 and P33/TO51/TI51/INTP3 pins for timer input, set PM34 and PM33
to 1. At this time, the output latches of P34 and P33 may be 0 or 1.
Figure 7-10. Format of Port Mode Register 3 (PM3)
Address: FF23H After reset: FFH R/W
Symbol
7 6 5 4 3 2 1 0
PM3
1
1
PM35 PM34 PM33 PM32 PM31
1
PM3n
P1n pin I/O mode selection (n = 1 to 5)
0
Output mode (output buffer on)
1
Input mode (output buffer off)