Renesas R5S72646 Doll User Manual


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Section 16 Renesas Serial Peripheral Interface
Page 836 of 2108 R01UH0134EJ0400 Rev. 4.00
Sep 24, 2014
SH7262 Group, SH7264 Group
If the SSL signal settings in the SPCMD in which 1 is assigned to the SSLKP bit are different
from the SSL signal output settings in the SPCMD to be used in the next transfer, this module
switches the SSL signal status to SSL signal assertion ((5) in figure 16.16) corresponding to the
command for the next transfer. Notice that if such an SSL signal switching occurs, the slaves that
drive the MISO signal compete, and the possibility arises of the collision of signal levels.
This module in master mode references within the module the SSL signal operation for the case
where the SSLKP bit is not used. Even when the CPHA bit in SPCMD is 0, this module can
accurately start serial transfers by asserting the SSL signal for the next transfer. For this reason,
burst transfers in master mode can be executed irrespective of CPHA bit settings (see section
16.4.8 (2), Slave Mode Operation).
(e) RSPCK Delay (t1)
The RSPCK delay value in master mode depends on SCKDEN bit settings in the command
register (SPCMD) and on clock delay register (SPCKD) settings. This module determines the
SPCMD to be referenced during serial transfer by pointer control, and determines an RSPCK
delay value during serial transfer by using the SCKDEN bit in the selected SPCMD and SPCKD,
as shown in table 16.8. For a definition of RSPCK delay, see section 16.4.4, Transfer Format.
Table 16.8 Relationship among SCKDEN and SPCKD Settings and RSPCK Delay Values
SCKDEN SPCKD RSPCK Delay Value
0 000 to 111 1 RSPCK
1 000 1 RSPCK
001 2 RSPCK
010 3 RSPCK
011 4 RSPCK
100 5 RSPCK
101 6 RSPCK
110 7 RSPCK
111 8 RSPCK