Renesas SH7781 用户手册

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页码 1692
23.   Serial Peripheral Interface (HSPI) 
Rev.1.00  Jan. 10, 2008  Page 1167 of 1658 
REJ09B0261-0100 
 
23.4.3
 
Timing Diagrams 
The following diagrams explain the timing relationship of all shift and sample processes in the 
HSPI. Figure 23.3 shows the conditions when FBS = 0, figure 23.4 shows the conditions when 
FBS = 0 (continuous transfer), figure 23.5 shows the conditions when FBS = 1, and figure 23.6 
shows the conditions when FBS = 1 (continuous transfer). It can be seen that if CLKP in SPCR is 
0, transmit data is shifted at the falling edge of HSPI_CLK and receive data is sampled at the 
rising edge of HSPI_CLK. The opposite is true when CLKP = 1. 
Data transfer cycle
HSPI_CLK (CLKP = 0)
HSPI_CLK (CLKP = 1)
1
4
3
2
8
7
6
5
HSPI_TX
MSB
6
5
4
3
2
1
LSB
MSB
6
5
4
3
2
1
LSB
*
HSPI_RX
HSPI_CS
 
Figure 23.3   Timing Conditions when FBS = 0 
HSPI_CLK (CLKP = 0)
HSPI_CLK (CLKP = 1)
1
8
..
2
9
16
..
10
HSPI_TX
MSB
6
LSB
MSB
6
LSB
MSB
6
LSB
MSB
6
LSB
*
HSPI_RX
HSPI_CS
Data transfer cycle
*
 
Figure 23.4   Timing Conditions when FBS = 0 (Continuous Transfer)