MC908GR8CDWE Datasheet, PDF (225/408 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

16.7 Port E
Freescale Semiconductor, Inc.
Input/Output Ports (I/O)
Port E
Port E is a 2-bit special-function port that shares two of its pins with the
serial communications interface (SCI) module.
16.7.1 Port E Data Register
The port E data register contains a data latch for each of the two port E
pins.
Address: $0008
Bit 7
6
Read: 0
0
Write:
Reset:
Alternate
Function:
5
4
3
2
0
0
0
0
Unaffected by reset
1
Bit 0
PTE1 PTE0
RxD
TxD
= Unimplemented
Figure 16-17. Port E Data Register (PTE)
PTE1 and PTE0 — Port E Data Bits
PTE1 and PTE0 are read/write, software programmable bits. Data
direction of each port E pin is under the control of the corresponding
bit in data direction register E.
NOTE:
Data direction register E (DDRE) does not affect the data direction of
port E pins that are being used by the SCI module. However, the DDRE
bits always determine whether reading port E returns the states of the
latches or the states of the pins. See Table 16-6.
RxD — SCI Receive Data Input
The PTE1/RxD pin is the receive data input for the SCI module. When
the enable SCI bit, ENSCI, is clear, the SCI module is disabled, and
the PTE1/RxD pin is available for general-purpose I/O. See Serial
Communications Interface (SCI).
MC68HC908GR8 — Rev 4.0
MOTOROLA
Input/Output Ports (I/O)
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Technical Data
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