PSC Registers—MBAR + 0x2000, 0x2200, 0x2400, 0x2600, 0x2800, 0x2C00
MPC5200B Users Guide, Rev. 1
Freescale Semiconductor 15-41
15.2.37 Rx FIFO Last Write Frame PTR (0x7C)—RFLWFPTR15.2.38 Tx FIFO Data (0x80)—TFDATA
Read - write register to access the internal TX FIFO Data register. Write to this register write data to the transmit FIFO. Additional the register
provide the possibility to read data back from the TX FIFO for debug issues. For more informations about the data format see Section 15.2.7,
Tx Buffer Register (0x0C)—TB.
15.2.39 Tx FIFO Status (0x84)—TFSTAT
For additional informations about the FIFO related status bits see Section 15.2.3, Status Register (0x04) — SR.
NOTE
To make sure that the PSC never lost the data in the FIFO, the PSC controller avoid writing to a full
FIFO or reading from an empty FIFO. Therefore the status bits in the FIFO STAT register never
reports an ERROR, UF or OF state. The SR register reports these errors.

Table15-65. Rx FIFO Last Write Frame PTR (0x7C)

msb 012345678 9 101112131415 lsb
RReserved LFP
W
RESET:000000000 0 0 000 0 0
Bit Name Description
0:3 — Reserved
4:15 LFP Last Frame Pointer. Not applicable to PSC FIFOs, since the PSCs do not recognize frame
formats in the serial data stream.

Table15-66. Tx FIFO STAT (0x84)

msb 01 2 345678 9101112131415 lsb
RReserved
Frame[3]
Frame[2]
Frame[1]
Frame[0]
Rese
rved
Error UF OF FR FULL
ALARM
EMPTY
W
RESET:00 0 000000 0 0 00 0 0 0
Bit Name Description
0:3 — Reserved
4:7 Frame[3 :0] Frame indicator. Not applicable to PSC FIFOs, since the PSCs do not recognize frame
formats in the serial data stream.
8—Reserved
9 Error FIFO error. A FIFO error has occurred due to either underflow, overflow, or read or write
pointer out of bounds.This bit is cleared by writing 1 to it.
10 UF Underflow. The read pointer has surpassed the write pointer due to the FIFO having been
read when it contained no data. This bit is cleared by writing 1 to it.
11 OF Overflow. The write pointer has surpassed the read pointer due to the FIFO having been
written when it was already completely full of data. This bit is cleared by writing 1 to it.
12 FR Frame ready. Not applicable to PSC FIFOs, since the PSCs do not recognize frame formats
in the serial data stream.
13 FULL Full. The FIFO is completely full of data.