Freescale Semiconductor MC68HC08KH12 manual Port Options, Port F Pin Functions, 204

When bit DDRFx is a logic one, reading address $0009 reads the PTFx data latch. When bit DDRFx is a logic zero, reading address $0009 reads the voltage level on the pin. The data latch can always be written, regardless of the state of its data direction bit. Table 12-7summarizes the operation of the port F pins.

		Table 12-7. Port F Pin Functions
			Accesses to	Accesses to PTE
DDRE	PTE	I/O Pin Mode	DDRE
Bit	Bit
			Read/Write	Read	Write
0	X(1)	Input, Hi-Z(2)	DDRF[7:0]	Pin	PTF[7:0](3)
1	X	Output	DDRF[7:0]	PTF[7:0]	PTF[7:0]

1.X = don’t care

2.Hi-Z = high impedance

3.Writing affects data register, but does not affect input.

12.9 Port Options

All pins of port A, port B and port C have programmable pullup resistors.

Port C also has LED drive capability.

12.9.1 Port Option Control Register (POC)

The pullup option for each port is controlled by one bit in the port option control register. One bit controls the LED drive configuration on port C.

Address:

Read:

Write:

Reset:

$001D
Bit 7	6	5	4	3	2	1	Bit 0
0	0	LDD	0	0	PCP	PBP	PAP
0	0	1	0	0	0	0	0
	= Unimplemented

Figure 12-22. Port Option Control Register (POC)

Advance Information	MC68HC(7)08KH12 — Rev. 1.1
204	Freescale Semiconductor