Spi Control Register 2 (Spixc2) - ROHS MC9S08QE128 Reference Manual

Serial Peripheral Interface (S08SPIV3)
Field
4 Master/Slave Mode Select
MSTR 0 SPI module configured as a slave SPI device
1 SPI module configured as a master SPI device
3 Clock Polarity — This bit effectively places an inverter in series with the clock signal from a master SPI or to a
CPOL slave SPI device. Refer to
0 Active-high SPI clock (idles low)
1 Active-low SPI clock (idles high)
2 Clock Phase — This bit selects one of two clock formats for different kinds of synchronous serial peripheral
CPHA devices. Refer to
0 First edge on SPSCK occurs at the middle of the first cycle of an 8-cycle data transfer
1 First edge on SPSCK occurs at the start of the first cycle of an 8-cycle data transfer
1 Slave Select Output Enable — This bit is used in combination with the mode fault enable (MODFEN) bit in
SSOE SPCR2 and the master/slave (MSTR) control bit to determine the function of the SS pin as shown in
0 LSB First (Shifter Direction)
LSBFE 0 SPI serial data transfers start with most significant bit
1 SPI serial data transfers start with least significant bit
MODFEN
0
0
1
1
Ensure that the SPI should not be disabled (SPE=0) at the same time as a bit change to the CPHA bit. These
changes should be performed as separate operations or unexpected behavior may occur.
15.4.2

SPI Control Register 2 (SPIxC2)

This read/write register is used to control optional features of the SPI system. Bits 7, 6, 5, and 2 are not
implemented and always read 0.
7
R 0
W
Reset 0
= Unimplemented or Reserved
274
Table 15-1. SPIxC1 Field Descriptions (continued)
Section 15.5.1, "SPI Clock
Section 15.5.1, "SPI Clock
Table 15-2. SS Pin Function
SSOE
0 General-purpose I/O (not SPI)
1 General-purpose I/O (not SPI)
0 SS input for mode fault
1 Automatic SS output
6 5
0 0
MODFEN
0 0
Figure 15-6. SPI Control Register 2 (SPIxC2)
MC9S08QE128 MCU Series Reference Manual, Rev. 2
Description
Formats" for more details.
Formats" for more details.
Master Mode
NOTE
4 3
BIDIROE
0 0
Slave Mode
Slave select input
Slave select input
Slave select input
Slave select input
2 1
0
SPISWAI
0 0
Freescale Semiconductor
Table 15-2.
0
SPC0
0