MCF548x Reference Manual, Rev. 3
27-16 Freescale Semiconductor

27.6.7 DSPI Rx FIFO Register (DRFR)

The DRFR provides a means to read the Rx FIFO. See Section 27.7.2.5, “Rx FIFO Buffering Mechanism

for a description of the Rx FIFO operations. 8- or 16-bit read accesses to the DRFR will read from the Rx

FIFO and update the counter and pointer.

26 CTCNT Clear SPI_TCNT. The CTCNT provides a means for host software to clear the SPI transfer counter.
The CTCNT bit clears the SPI_TCNT field in the DTCR register. The SPI_TCNT field is cleared
before transmission of the current SPI frame begins.
0 Do not clear DTCR[SPI_TCNT]
1 Clear DTCR[SPI_TCNT]
25–22,
20, 17
Reserved, should be cleared.
21, 19,
18, 16
CSnDSPI chip select. The CSn bits select which DSPICSn signals will be asserted for the transfer.
0 Negate the DSPICSn signal
1 Assert the DSPICSn signal
15–0 TXDATA Transmit data. The TXDATA field holds SPI data to be transferred according to the associated SPI
command.
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16
R0000000000000000
W
Reset0000000000000000
1514131211109876543210
RRXDATA
W
Reset0000000000000000
Reg
Addr
MBAR + 0x8A38

Figure 27-8. DSPI Rx FIFO Register (DRFR)

Table 27-11. DRFR Field Descriptions

Bits Name Description
31–16 Reserved, should be cleared.
15–0 RXDATA Received data. The RXDATA field contains the SPI data from the Rx FIFO entry pointed to
by the receive next data pointer.

Table 27-10. DTFR Field Descriptions (Continued)

Bits Name Description