D12320VF25IV Datasheet, PDF (457/1304 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 9 I/O Ports
Port E MOS Pull-Up Control Register (PEPCR)
Bit
:
7
6
5
4
3
2
1
0
PE7PCR PE6PCR PE5PCR PE4PCR PE3PCR PE2PCR PE1PCR PE0PCR
Initial value :
0
0
0
0
0
0
0
0
R/W
: R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
PEPCR is an 8-bit readable/writable register that controls the MOS input pull-up function
incorporated into port E on an individual bit basis.
When a PEDDR bit is cleared to 0 (input port setting) in mode 4, 5, or 6 with 8-bit bus mode
selected, or in mode 7, setting the corresponding PEPCR bit to 1 turns on the MOS input pull-up
for the corresponding pin.
PEPCR is initialized to H'00 by a reset, and in hardware standby mode. It retains its prior state in
software standby mode.
9.12.3 Pin Functions
Modes 4 to 6: In modes 4 to 6, when 8-bit access is designated and 8-bit bus mode is selected,
port E pins are automatically designated as I/O ports. Setting a PEDDR bit to 1 makes the
corresponding port E pin an output port, while clearing the bit to 0 makes the pin an input port.
When 16-bit bus mode is selected, the input/output direction specification by PEDDR is ignored,
and port E is designated for data I/O.
Port E pin functions in modes 4 to 6 are shown in figure 9.20.
Rev.6.00 Sep. 27, 2007 Page 425 of 1268
REJ09B0220-0600