Smc Uart Txbd - Motorola MPC8260 PowerQUICC II User Manual

Part IV. Communications Processor Module
E
Status 0
Length
Pointer
E
Status 0
Length
Pointer
E
Status 0
Length
Pointer
E
Status 1
Length
Pointer
10 Characters
Characters
Received by UART
Time

26.3.10 SMC UART TxBD

Data is sent to the CP for transmission on an SMC channel by arranging it in buffers
referenced by the channel TxBD table. Using the BDs, the CP confirms transmission or
indicates error conditions so that the processor knows the buffers have been serviced.
26-16
Receive BD 0
ID
0
0008
32-Bit Buffer Pointer
Receive BD 1
ID
1
0002
32-Bit Buffer Pointer
Receive BD 2
ID FR
0 1
0004
32-Bit Buffer Pointer
Receive BD 3
XXXX
32-Bit Buffer Pointer
Figure 26-7. RxBD Example
MPC8260 PowerQUICC II UserÕs Manual
MRBLR = 8 Bytes for this SMC
Buffer
Byte 1
Byte 2
Buffer Full
etc.
Byte 8
Buffer
Byte 9
Byte 10
Idle Time-Out
Occurred
Empty
Buffer
Byte 1
Byte 2
Byte 4 has
Byte 3
Framing Error
Byte 4 Error!
Empty
Buffer
Byte 5
Additional Bytes
are Stored Unless
Reception
Idle Count Expires
Still in Progress
(MAX_IDL)
with this Buffer
Long Idle Period
8 Bytes
8 Bytes
8 Bytes
8 Bytes
5 Characters
Fourth Character Present
has Framing Error! Time
MOTOROLA