HD64F2149 Datasheet, PDF (245/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

Port 3
P37 (I/O)/HDB7 (I/O)/SERIRQ (I/O)
P36 (I/O)/HDB6 (I/O)/LCLK (Input)
P35 (I/O)/HDB5 (I/O)/LRESET (Input)
P34 (I/O)/HDB4 (I/O)/LFRAME (Input)
P33 (I/O)/HDB3 (I/O)/LAD3 (I/O)
P32 (I/O)/HDB2 (I/O)/LAD2 (I/O)
P31 (I/O)/HDB1 (I/O)/LAD1 (I/O)
P30 (I/O)/HDB0 (I/O)/LAD0 (I/O)
Figure 8.11 Port 3 Pin Functions (Modes 2 and 3 (EXPE = 0))
8.4.4 MOS Input Pull-Up Function
Port 3 has a built-in MOS input pull-up function that can be controlled by software. This MOS
input pull-up function can be used in modes 2 and 3 (when EXPE = 0), and can be specified as on
or off on a bit-by-bit basis.
When a P3DDR bit is cleared to 0 in mode 2 or 3 (when EXPE = 0), setting the corresponding
P3PCR bit to 1 turns on the MOS input pull-up for that pin.
The MOS input pull-up function is in the off state after a reset and in hardware standby mode. The
prior state is retained in software standby mode.
Table 8.7 summarizes the MOS input pull-up states.
Table 8.7 MOS Input Pull-Up States (Port 3)
Mode
Reset
Hardware
Standby Mode
Software
Standby Mode
1, 2, 3 (EXPE = 1) Off
Off
Off
2, 3 (EXPE = 0) Off
Off
On/Off
Legend:
Off: MOS input pull-up is always off.
On/Off: On when P3DDR = 0 and P3PCR = 1; otherwise off.
In Other
Operations
Off
On/Off
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