MC68HC708MP16 Datasheet, PDF (330/398 Pages) Freescale Semiconductor, Inc – Microcontrollers

Input/Output (I/O) Ports
When bit DDREx is a logic 1, reading address $0004 reads the PTEx
data latch. When bit DDREx is a logic 0, reading address $0004 reads
the voltage level on the pin. The data latch can always be written,
regardless of the state of its data direction bit. Table 15-3 summarizes
the operation of the port E pins.
Table 15-5. Port E Pin Functions
DDRE PTE
Bit
Bit
I/O Pin Mode
0
X⁽¹⁾
Input, Hi-Z⁽²⁾
Accesses to
DDRE
Read/Write
DDRE[7:0]
1
X
Output
DDRE[7:0]
1. X = don’t care
2. Hi-Z = high impedance
3. Writing affects data register, but does not affect input.
Accesses to PTE
Read
Pin
PTE[7:0]
Write
PTE[7:0]⁽³⁾
PTE[7:0]
15.8 Port F
Port F is a 6-bit special function port that shares four of its pins with the
serial peripheral interface module (SPI) and two pins with the serial
communications interface (SCI).
15.8.1 Port F Data Register
The port F data register (PTF) contains a data latch for each of the six
port F pins.
Address:
Read:
Write:
Reset:
$0005
Bit 7
0
6
5
0
PTF5
= Unimplemented
4
3
PTF4 PTF3
Unaffected by reset
2
PTF2
1
PTF1
Bit 0
PTF0
Figure 15-16. Port F Data Register (PTF)
Technical Data
330
Input/Output (I/O) Ports
MC68HC708MP16 — Rev. 3.1
Freescale Semiconductor