Input/Output (I/O) Ports
Technical Data MC68HC908AB32 — Rev. 1.0
326 Input/Output (I/O) Ports MOTOROLA
17.7 Port E
Port E is an 8-bit special function port that shares two of its pins with the
timer interface module (TIMA), two of its pins with the serial
communications interface module (SCI) and four of its pins with the
serial peripheral interface module (SPI).
17.7.1 Port E Data Register (PTE)
The port E data register contains a data latch for each of the eight port E
pins.
PTE[7:0] — Port E Data Bits
These read/write bits are software programmable. Data direction of
each port E pin is under the control of the corresponding bit in data
direction register E. Reset has no effect on port E data.
SPSCK — SPI Serial Clock
The PTE7/SPSCK pin is the serial clock input of a SPI slave module
and serial clock output of a SPI master modules. When the SPE bit is
clear, the PTE7/SPSCK pin is available for general-purpose I/O. See
16.14.1 SPI Control Register.
MOSI — Master Out/Slave In
The PTE6/MOSI pin is the master out/slave in terminal of the SPI
module. When the SPE bit is clear, the PTE6/MOSI pin is available for
general-purpose I /O. See 16.14.1 SPI Control Register.
Address: $0008
Bit 7 654321Bit 0
Read:
PTE7 PTE6 PTE5 PTE4 PTE3 PTE2 PTE1 PTE0
Write:
Reset: Unaffected by reset
Alternative Function: SPSCK MOSI MISO SS TACH1 TACH0 RxD TxD
Figure 17-15. Port E Data Register (PTE)