CHAPTER 11 SERIAL INTERFACE CSI10
Preliminary User’s Manual U19014EJ1V0UD
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(3) Port mode register 1 (PM1)
This register sets port 1 input/output in 1-bit units.
When using P10/SCK10 as the clock output pin of the serial interface, clear PM10 to 0, and set the output latches
of P10 to 1.
When using P12/SO10 as the data output pin of the serial interface, clear PM12 and the output latch of P12 to 0.
When using P10/SCK10 as the clock input pin of the serial interface, and P11/SI10 as the data input pin, set
PM10 and PM11 to 1. At this time, the output latches of P10 and P11 may be 0 or 1.
PM1 can be set by a 1-bit or 8-bit memory manipulation instruction.
Reset signal generation sets this register to FFH.
Figure 11-4. Format of Port Mode Register 1 (PM1)
7
PM17
6
PM16
5
PM15
4
PM14
3
PM13
2
PM12
1
PM11
0
PM10
Symbol
PM1
Address: FF21H After reset: FFH R/W
PM1n
0
1
P1n pin I/O mode selection (n = 0 to 7)
Output mode (output buffer on)
Input mode (output buffer off)
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