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CHAPTER 6 16-BIT TIMER 90
User’s Manual U15075EJ2V1UD
126
(3) Port mode registers 2, 3 (PM2, PM3)
PM2 and PM3 are used to set each bit of ports 2 and 3 to input or output.
When the P26/TO90 pin is used for timer output, reset the output latch of P26 and PM26 to 0; when pin
P21/BZO90 is used for buzzer output, reset the output latch of P26 and PM26 to 0.
When using the P30/INTP0/CPT90 pin as a capture input, set PM30 to 1.
PM2 and PM3 are set with a 1-bit or 8-bit memory manipulation instruction.
RESET input sets PM2 and PM3 to FFH.
Figure 6-4. Format of Port Mode Registers 2, 3
PMmn
Pmn pin I/O mode (mn = 20 to 26, 30 to 33)
Output mode (output buffer ON)
Input mode (output buffer OFF)
0
1
1
1
1
1
PM33
PM32
PM31
PM30
PM3
Symbol
Address
After reset
R/W
FF23H
FFH
R/W
6
7
5
4
3
2
1
0
1
PM26
PM25
PM24
PM23
PM22
PM21
PM20
PM2
Symbol
Address
After reset
R/W
FF22H
FFH
R/W
6
7
5
4
3
2
1
0