Datasheet

Section 9 I/O Ports
Rev.6.00 Sep. 27, 2007 Page 380 of 1268
REJ09B0220-0600
9.5.2 Register Configuration
Table 9.8 shows the port 4 register configuration. Port 4 is an input-only port, and does not have a
data direction register or data register.
Table 9.8 Port 4 Register
Name Abbreviation R/W Initial Value Address
*
Port 4 register PORT4 R Undefined H'FF53
Note: * Lower 16 bits of the address.
Port 4 Register (PORT4): The pin states are always read when a port 4 read is performed.
Bit : 7 6 5 4 3 2 1 0
P47 P46 P45 P44 P43 P42 P41 P40
Initial value : —
*
—
*
—
*
—
*
—
*
—
*
—
*
—
*
R/W : R R R R R R R R
Note: * Determined by state of pins P4
7
to P4
0
.
9.5.3 Pin Functions
Port 4 pins also function as A/D converter analog input pins (AN
0
to AN
7
) and D/A converter
analog output pins (DA
0
and DA
1
).