CHAPTER 6 16-BIT TIMER
(3) Port mode register 2 (PM2)
PM2 is used to set each bit of port 3 to input or output.
When pin P26/ITO90 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.
PM2 is set with a 1-bit or 8-bit memory manipulation instruction.
RESET input sets PM2 to FFH.
Figure 6-4. Format of Port Mode Register 2
Address After reset R/W
FF22H FFH R/W
Symbol
PM2
7
1
6
5
4
3
0
2
1
PM26
PM25
PM24
PM23
PM22
PM21
PM20
P2n pin I/O mode (n =1, 6)
PM2n
0
1
Output mode (output buffer ON)
Input mode (output buffer OFF)
User’s Manual U15075EJ1V0UM00
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NEC [ NEC ]
