Advertisement
10.12.2 Register Configuration
Table 10-20 shows the port F register configuration.
Table 10-20 Port F Registers
Name
Port F data direction register
Port F data register
Port F register
Notes: 1. Lower 16 bits of the address.
2. Initial value depends on the mode.
Port F Data Direction Register (PFDDR)
Bit
:
PF7DDR PF6DDR PF5DDR PF4DDR PF3DDR PF2DDR PF1DDR PF0DDR
Modes 4 to 6
Initial value :
R/W
:
Mode 7
Initial value :
R/W
:
PFDDR is an 8-bit write-only register, the individual bits of which specify input or output for the
pins of port F. PFDDR cannot be read; if it is, an undefined value will be read.
PFDDR is initialized by a power-on reset, and in hardware standby mode, to H'80 in modes 4 to
6, and to H'00 in mode 7. It retains its prior state by a manual reset or in software standby mode.
The OPE bit in SBYCR is used to select whether the bus control output pins retain their output
state or become high-impedance when a transition is made to software standby mode.
• Modes 4 to 6
Pin PF7 functions as the ø output pin when the corresponding PFDDR bit is set to 1, and as an
input port when the bit is cleared to 0.
The input/output direction specified by PFDDR is ignored for pins PF6 to PF3, which are
automatically designated as bus control outputs (AS, RD, HWR, and LWR). PF6 functions as a
bus control output (LCAS) by setting of the bus controller.
Abbreviation
PFDDR
PFDR
PORTF
7
6
1
0
W
W
0
0
W
W
R/W
W
R/W
R
5
4
0
0
W
W
0
0
W
W
Initial Value
H'80/H'00 *
2
H'00
Undefined
3
2
0
0
W
W
0
0
W
W
Address *
1
H'FE3E
H'FF0E
H'FFBE
1
0
0
0
W
W
0
0
W
W
393
Advertisement
