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Deserial Serial Peripheral Interface (DSPI)
MPC5644A Microcontroller Reference Manual, Rev. 6
1332
Freescale Semiconductor
10. Enable DMA channel by enabling the DMA enable request for the DMA channel assigned to the
DSPI TX FIFO, and RX FIFO by setting the corresponding DMA set enable request bit.
11. Enable serial transmission and serial reception of data by clearing the EOQF bit.
30.10.2 Switching master and slave mode
When changing modes in the DSPI, follow the steps below to guarantee proper operation.
1. Halt the DSPI by setting DSPI_MCR[HALT].
2. Clear the transmit and receive FIFOs by writing a 1 to the CLR_TXF and CLR_RXF bits in
DSPI_MCR.
3. Set the appropriate mode in DSPI_MCR[MSTR] and enable the DSPI by clearing
DSPI_MCR[HALT].
30.10.3 Baud rate settings
shows the baud rate that is generated based on the combination of the baud rate prescaler PBR
and the baud rate scaler BR in the DSPI_CTAR registers. The values calculated assume a 100 MHz system
frequency and the double baud rate DBR bit is clear.
Table 30-45. Baud rate values (bit/s)
Baud rate divider prescaler values
2
3
5
7
Ba
ud
r
a
te
sca
ler
v
a
lues
2
25.0M
16.7M
10.0M
7.14M
4
12.5M
8.33M
5.00M
3.57M
6
8.33M
5.56M
3.33M
2.38M
8
6.25M
4.17M
2.50M
1.79M
16
3.12M
2.08M
1.25M
893k
32
1.56M
1.04M
625k
446k
64
781k
521k
312k
223k
128
391k
260k
156k
112k
256
195k
130k
78.1k
55.8k
512
97.7k
65.1k
39.1k
27.9k
1024
48.8k
32.6k
19.5k
14.0k
2048
24.4k
16.3k
9.77k
6.98k
4096
12.2k
8.14k
4.88k
3.49k
8192
6.10k
4.07k
2.44k
1.74k
16384
3.05k
2.04k
1.22k
872
32768
1.53k
1.02k
610
436
Summary of Contents for MPC5644A
Page 2: ...MPC5644A Microcontroller Reference Manual Rev 6 2 Freescale Semiconductor...
Page 24: ...MPC5644A Microcontroller Reference Manual Rev 6 24 Freescale Semiconductor...
Page 26: ...MPC5644A Microcontroller Reference Manual Rev 6 26 Freescale Semiconductor...
Page 52: ...Introduction MPC5644A Microcontroller Reference Manual Rev 6 52 Freescale Semiconductor...
Page 56: ...Memory Map MPC5644A Microcontroller Reference Manual Rev 6 56 Freescale Semiconductor...
Page 1228: ...Decimation Filter MPC5644A Microcontroller Reference Manual Rev 6 1228 Freescale Semiconductor...
Page 1440: ...FlexCAN Module MPC5644A Microcontroller Reference Manual Rev 6 1440 Freescale Semiconductor...