UPD78F0411GA-GAM-AX Datasheet, PDF (324/564 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

CHAPTER 13 SERIAL INTERFACE UART0
(5) Port mode register 1 (PM1)
This register sets port 1 input/output in 1-bit units.
When using the P13/TxD0/KR4/<TxD6> pin for serial interface data output, clear PM13 to 0. The output latch of
P13 at this time may be 0 or 1.
When using the P12/RxD0/KR3/<RxD6> pin for serial interface data input, set PM12 to 1. The output latch of
P12 at this time 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.
Remark The functions within arrowheads (< >) can be assigned by setting the input switch control register (ISC).
Figure 13-6. 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
1
1
PM1n
0
1
P1n pin I/O mode selection (n = 2, 3)
Output mode (output buffer on)
Input mode (output buffer off)
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User’s Manual U18698EJ1V0UD