Software Environment
MCF548x Reference Manual, Rev. 3
Freescale Semiconductor 26-51

26.7.2.3 Modem16 Mode

The configuration sequence in modem16 mode is almost the same as in modem8 mode except that the first

write value to the SIM[2:0] in PSCSICR should be 3’b010.

26.7.2.4 AC97 Mode

Applying a 12.288 MHz clock to the PSCBCLK input and programming the control registers are required

to initialize in AC97 mode. The following table describes a sample sequence.

5 PSCTFCR 0F WRITE TAG=00 Not EOF
FRMEN=1 Enable frame mode
GR[2:0]=100 Granularity is 16 byte
6 PSCRFAR 00F0 ALARM[8:0]=0F0 Request is asserted if # of data >= 240
7 PSCTFAR 00F0 ALARM[8:0]=0F0 Request is asserted if # of empty >= 240
8 PSCCR 05 TC=01 Enable transmitter
RC=01 Enable receiver

Table 26-43. A Sample Initialization Sequence for AC97 Mode

Step
No. Register Value Details Meaning
1 PSCSICR 03 ACRB=1 Not cold reset
AWR=0 Not warm reset
SIM[2:0]=011 AC97 mode
2 PSCCR 20 MISC=010 Reset receiver and RxFIFO
30 MISC=011 Reset transmitter and TxFIFO
40 MISC=100 Reset all error status
3 PSCIMR 0300 IPC=0 Disable input port change interrupt
RxRDY or FU=1 Enable receiver interrupt/request
TxRDY=1 Enable transmitter interrupt/request
4 PSCRFCR 0F WRITE TAG = 00 Not EOF
FRMEN=1 Enable frame mode
GR[2:0]=100 Granularity is 4 byte
5 PSCTFCR 0F WRITE TAG = 00 Not EOF
FRMEN=1 Enable frame mode
GR[2:0]=100 Granularity is 16 byte

Table 26-42. Sample Initialization Sequence for Modem8 Mode (Continued)

Step
No. Register Value Details Meaning