PXD10RM Datasheet, PDF (295/1332 Pages) Freescale Semiconductor, Inc – PXD10 Microcontroller

Table 11-5. DSPIx_CTARn Field Descriptions (continued)
Field
12–13
PDT[0:1]
Descriptions
Delay after Transfer Prescaler. The PDT field selects the prescaler value for the delay 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. The PDT field is only used in Master Mode. The table below lists the prescaler values.
See the DT[0:3] field description for details on how to compute the Delay after Transfer.
PDT
00
01
10
11
Delay after Transfer Prescaler Value
1
3
5
7
14–15
PBR[0:1]
Baud Rate Prescal. The PBR field selects the prescaler value for the baud rate. This field is only used
in Master Mode. The Baud Rate is the frequency of the Serial Communications Clock (SCK). The
system clock is divided by the prescaler value before the baud rate selection takes place. The Baud
Rate Prescaler values are listed in the table below. See the BR[0:3] field description for details on
how to compute the baud rate.
PBR
00
01
10
11
Baud Rate Prescaler Value
2
3
5
7
16–19
CSSCK[0:3]
PCS to SCK Delay Scaler. The CSSCK field selects the scaler value for the PCS to SCK delay. This
field is only used in Master Mode. The PCS to SCK Delay is the delay between the assertion of PCS
and the first edge of the SCK. Table 11-8 list the scaler values.The PCS to SCK Delay is a multiple
of the system clock period and it is computed according to the following equation:
t_CSC
=
-----¹-----  PCSSCK  CSSCK
f_SYS
Eqn. 11-1
20–23
ASC[0:3]
After SCK Delay Scaler. The ASC field selects the scaler value for the After SCK Delay. This field is
only used in Master Mode. The After SCK Delay is the delay between the last edge of SCK and the
negation of PCS. Table 11-9 list the scaler values.The After SCK Delay is a multiple of the system
clock period, and it is computed according to the following equation:
t_ASC
=
-----¹-----  PASC  ASC
f_SYS
Eqn. 11-2
Freescale Semiconductor
PXD10 Microcontroller Reference Manual, Rev. 1
Preliminary—Subject to Change Without Notice
11-13