Freescale Semiconductor MPC5200B ユーザーズマニュアル
PSC Registers—MBAR + 0x2000, 0x2200, 0x2400, 0x2600, 0x2800, 0x2C00
MPC5200B Users Guide, Rev. 1
Freescale Semiconductor
15-39
15.2.32
Rx FIFO Control (0x68)—RFCNTL
15.2.33
Rx FIFO Alarm (0x6E)—RFALARM
Bit
Name
Description
0:3
—
Reserved
4:7
Frame[3:0]
Frame indicator. Not applicable to PSC FIFO’s, since the PSCs do not recognize frame
formats in the serial data stream.
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 a ‘1’ to it.
pointer out of bounds.This bit is cleared by writing a ‘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 a ‘1’ to it.
read when it contained no data. This bit is cleared by writing a ‘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 a ‘1’ to it.
written when it was already completely full of data. This bit is cleared by writing a ‘1’ to it.
12
FR
Frame ready. Not applicable to PSC FIFO’s, since the PSCs do not recognize frame
formats in the serial data stream.
formats in the serial data stream.
13
FULL
Full. The FIFO is completely full of data.
14
ALARM
for a detailed description.
15
EMPTY
FIFO Empty. The FIFO is completely empty.
Table 15-60. Rx FIFO Control (0x68)
msb 0
1
2
3
4
5
6
7 lsb
R
Reserved
WFR
COMP
FRAME
GR[2:0]
W
RESET:
0
0
0
0
1
0
0
1
Bit
Name
Description
0:1
—
Reserved
2
WFR
Write frame. Not applicable to PSC FIFOs, since the PSCs do not recognize frame formats in
the serial data stream.
the serial data stream.
3
COMP
Re-enable requests on frame transmission completion. Not applicable to PSC FIFOs, since
the PSCs do not recognize frame formats in the serial data stream.
the PSCs do not recognize frame formats in the serial data stream.
4
FRAME
Frame mode enable. THIS BIT MUST BE CLEARED BY WRITING A ‘0’ TO IT, since the PSCs
do not recognize frame formats in the serial data stream.
do not recognize frame formats in the serial data stream.
5:7
GR[2:0]
Last transfer granularity. Amount of data remaining in the Rx FIFO at which the ALARM bit in
the status register will go low/inactive. See
the status register will go low/inactive. See
for details.
Table 15-61. Rx FIFO Alarm (0x6E)
msb 0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 lsb
R
Reserved
ALARM
W
RESET:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0