Motorola MPC860 PowerQUICC User Manual page 835

31.4.1.2 SPI Examples with Different SPMODE[LEN] Values
The examples below show how SPMODE[LEN] is used to determine character length. To
help map the process, the conventions shown in Table 31-2 are used in the examples.
Convention
1
Both __ and _ are used to aid readability.
For all examples below, assume the memory contains the following binary image:
msb
Example 1
with LEN=4 (data size=5), the following data is selected:
msb
with REV=0, the order of the string appearing on the line is:
first
with REV=1, the order of the string appearing on the line is:
first
Example 2
with LEN=7 (data size=8), the following data is selected:
msb
with REV=0, the string transmitted is:
first
with REV=1, the string is transmitted:
first
Example 3
with LEN=0xC (data size=13), the following data is selected:
msb
with REV=0, the string transmitted:
first
with REV=1, the string is transmitted:
first
MOTOROLA
Table 31-2. Example Conventions
g v
Ð
x
1
__
1
_
ghij_klmn__opqr_stuv
xxxj_klmn__xxxr_stuv
nmlk_j__vuts_r
j_klmn__r_stuv
ghij_klmn__opqr_stuv
nmlk_jihg__vuts_rqpo
ghij_klmn__opqr_stuv
ghij_klmn__xxxr_stuv
nmlk_jihg__vuts_r
ghij_klmn__r_stuv
Chapter 31. Serial Peripheral Interface
Part V. The Communications Processor Module
Description
Binary symbols
Deleted bit
Original byte boundary
Original 4-bit boundary.
lsb
lsb
last
last
lsb
last
last
lsb
last
last
31-9