Table 613. Dspi Sck Duty Cycle - STMicroelectronics SPC572L series Reference Manual

Deserial Serial Peripheral Interface (DSPI)
Field
PCS to SCK Delay Scaler. (Master mode only)
Selects the scaler value for the PCS to SCK delay.
PCS to SCK Delay is the delay between the assertion of PCS and the first edge of the SCK. The
delay is a multiple of the protocol clock period calculated by:
16–19
t
CSSCK
CSC
Table 614
Refer to
In TSB mode, the field has no effect.
After SCK Delay Scaler. (Master mode only)
Selects the scaler value for the After SCK Delay.
The After SCK Delay is the delay between the last edge of SCK and the negation of PCS. The
20–23
delay is a multiple of the protocol clock period calculated by:
ASC
t
ASC
See Delay Scaler Encoding table in CTARn[CSSCK] bit field description for scaler values.
Refer to
Delay After Transfer Scaler (Master mode only)
Selects the Delay after Transfer Scaler.
The Delay after Transfer is the time between the negation of the PCS signal at the end of a frame
and the assertion of PCS at the beginning of the next frame.
In the Continuous Serial Communications Clock operation, the DT value is fixed to one SCK
clock period.
24–27
The Delay after Transfer is a multiple of the protocol clock period calculated by:
DT
t = (1/f
DT
See Delay Scaler Encoding table in CTARn[CSSCK] bit field description for scaler values.
In the TSB mode, the Delay after Transfer is equal to a number formed by concatenation of the
PDT and DT fields plus 1 of the SCK clock periods.
Refer to
Baud Rate Scaler. (Master mode only)
Selects the scaler value for the baud rate.
28–31
The prescaled protocol clock is divided by the Baud Rate Scaler to generate the frequency of the
SCK. The baud rate is calculated by:
BR
SCK baud rate = (f
Table 615
1150/2058
Table 612. DSPI_CTARn field descriptions(Continued)
= (1/f ) x PCSSCK x CSSCK
P
lists the delay scaler values.
Section 46.5.5.2: PCS to SCK delay (tCSC)
= (1/f ) x PASC x ASC
P
Section 46.5.5.3: After SCK delay (tASC)
) × PDT × DT
P
Section 46.5.5.2: PCS to SCK delay (tCSC)
/PBR) × [(1+DBR)/BR]
P
lists the baud rate scaler values.

Table 613. DSPI SCK duty cycle

DBR
0
1
1
1
1
1
Description
for more details.
CPHA
any
0
0
0
0
1
DocID027809 Rev 4
for more details.
for more details.
PBR SCK duty cycle
any
00
01
10
11
00
RM0400
50/50
50/50
33/66
40/60
43/57
50/50