■
Block Diagram of Port 4
PDR read
PDR read
(when read-modify-write is
performed)
PDR write
DDR write
DDR read
OUT read
OUT write
■
Registers of Port 4
The registers PDR4, DDR4, and OUT4 are associated with port 4.
The bits of these registers correspond to the pins of port 4 in one-to-one correspondence.
Table 4.4-2 tabulates the correspondence between the pins and the bits of the port 4 registers.
Table 4.4-2 Correspondence between the Pins and the Bits of the Port 4 Register
Port name
PDR4, DDR4, OUT4
Port 4
Pin corresponding to bit
Figure 4.4-1 Block Diagram of Port 4
A/D converter
channel select
To A/D
converter's
analog input
PDR
Output latch
DDR
Stop mode
(SPL = 1)
OUT
Bits of associated registers and corresponding pins
bit7
-
A/D converter enable bit
Stop mode (SPL = 1)
Pch
Nch
bit6
bit5
bit4
-
-
-
CHAPTER 4 I/O PORTS
Pins
bit3
bit2
bit1
P43
P42
P41
bit0
P40
91