mc9s08ac16 Freescale Semiconductor, Inc, mc9s08ac16 Datasheet - Page 104

• Manufacturer Part Number: mc9s08ac16
• Description: Hcs08 Microcontrollers 8-bit Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

1
1
Chapter 6 Parallel Input/Output
6.7.11
Port F parallel I/O function is controlled by the registers listed below.
104
Bits 7, 3 and 2 are reserved bits that must always be written to 0.
Bits 7, 3 and 2 are reserved bits that must always be written to 0.
PTFDDn
Reset
Reset
6:4, 1:0
6:4, 1:0
PTFDn
Field
Field
W
W
R
R
Port F I/O Registers (PTFD and PTFDD)
Port F Data Register Bits— For port F pins that are inputs, reads return the logic level on the pin. For port F
pins that are configured as outputs, reads return the last value written to this register.
Writes are latched into all bits of this register. For port F pins that are configured as outputs, the logic level is
driven out the corresponding MCU pin.
Reset forces PTFD to all 0s, but these 0s are not driven out the corresponding pins because reset also configures
all port pins as high-impedance inputs with pullups disabled.
Data Direction for Port F Bits — These read/write bits control the direction of port F pins and what is read for
PTFD reads.
0 Input (output driver disabled) and reads return the pin value.
1 Output driver enabled for port F bit n and PTFD reads return the contents of PTFDn.
R
R
0
0
7
7
PTFDD6
PTFD6
0
0
6
6
Figure 6-36. Data Direction for Port F (PTFDD)
Table 6-27. PTFDD Register Field Descriptions
Table 6-26. PTFD Register Field Descriptions
Figure 6-35. Port F Data Register (PTFD)
PTFDD5
MC9S08AC16 Series Data Sheet, Rev. 0
PTFD5
0
0
5
5
PRELIMINARY
PTFDD4
PTFD4
0
0
4
4
Description
Description
R
R
3
0
3
0
1
R
R
0
0
2
2
1
PTFDD1
Freescale Semiconductor
PTFD1
0
0
1
1
PTFDD0
PTFD0
0
0
0
0