Renesas H8S/2318 series, Hardware Manual

Page: 305 / 1121

Rev. 5.00, 12/03, page 275 of 1088
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 PEDDR bits are 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 bits to 1 turns on the MOS input pull-up
for the corresponding pins.
PEPCR is initialized to H'00 by a reset, and in hardware standby mode. It retains its prior state in
software standby mode.
8.10.3 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 PEDDR bits to 1 makes the
corresponding port E pins output ports, while clearing the bits to 0 makes the pins input ports.
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 8-21.
PE7 (I/O)
PE6 (I/O)
PE5 (I/O)
PE4 (I/O)
PE3 (I/O)
PE2 (I/O)
PE1 (I/O)
PE0 (I/O)
Port E
D7 (I/O)
D6 (I/O)
D5 (I/O)
D4 (I/O)
D3 (I/O)
D2 (I/O)
D1 (I/O)
D0 (I/O)
8-bit bus mode 16-bit bus mode
Figure 8-21 Port E Pin Functions (Modes 4 to 6)