Processor Users Manual

28-8 MPC8260 PowerQUICC II UserÕs Manual MOTOROLA
Part IV. Communications Processor Module
Fields in the TODR are described in Table 28-4
28.6 FCC Buffer Descriptors
Data associated with each FCC channel is stored in buffers. Each buffer is referenced by a
buffer descriptor (BD) that can be anywhere in external memory.
The BD table forms a circular queue with a programmable length. The user can program
the start address of each channel BD table anywhere in memory. See Figure 28-3.
Bits 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Field TOD Ñ
Reset 0000_0000_0000_0000
R/W R/W
Address 0x11308 (FTODR1), 0x11328 (FTODR2), 0x11328 (FTODR3)
Table 28-3. FCC Transmit-on-Demand Register (TODR)
Table 28-4. TODR Field Descriptions
Field Name Description
0 TOD Transmit on demand
0 Normal polling.
1 The CP gives high priority to the current TxBD and begins sending the frame does without waiting
for the normal polling time to check TxBD[R]. TOD is cleared automatically.
1Ð15 Ñ Reserved, should be cleared.