MC68HC908GR8A_07 Datasheet, PDF (129/260 Pages) Freescale Semiconductor, Inc – Microcontrollers

Port E
When bit DDREx is a 1, reading address $0008 reads the PTEx data latch. When bit DDREx is a 0,
reading address $0008 reads the voltage level on the pin. The data latch can always be written,
regardless of the state of its data direction bit. Table 12-6 summarizes the operation of the port E pins.
Table 12-6. Port E Pin Functions
DDRE
PTE
Bit
Bit
I/O Pin
Mode
Accesses to DDRE
Read/Write
0
X⁽¹⁾
Input, Hi-Z⁽²⁾
DDRE1–DDRE0
1
X
Output
DDRE1–DDRE0
1. X = Don’t care
2. Hi-Z = High impedance
3. Writing affects data register, but does not affect input.
Accesses to PTE
Read
Write
Pin
PTE1–PTE0⁽³⁾
PTE1–PTE0
PTE1–PTE0
MC68HC908GR8A • MC68HC908GR4A Data Sheet, Rev. 5
Freescale Semiconductor
129