Datasheet

____________________________________________________ DS34S101, DS34S102, DS34S104, DS34S108
Rev: 032609 76 of 198
10.6.11.12 CPU to TDM Flow
The Rx arbiter polls the CPU-to-TDM queue for new packets waiting in the SDRAM to be processed. If the queue
level is greater than zero and there are no buffers pending in the Rx FIFO or the cross-connect queue, the Rx
arbiter extracts the pointer and copies the relevant data from the SDRAM buffer to the appropriate payload-type
machine. The arbiter then checks whether the CPU Rx return queue is not full to return the pointer. If the return
queue is full, the arbiter keeps the pointer and does not poll the CPU-to-TDM queue until it succeeds in returning
the pointer. After returning the pointer to the CPU Rx return queue for reuse, the arbiter is ready to take another
pointer from the CPU-to-TDM queue.
The CPU-to-TDM queue and the CPU Rx return queue can contain up to 32 pointers each. Section 11.4.6
describes the pool and queue registers.
Figure 10-55. CPU-to-TDM Flow
CPU TO TDM
QUEUE
CPU
RX
RETURN
QUEUE
SDRAM
RX
AAL1
RX
ARBITER
DATA
LOOP CLOSED BY THE CPU
TDMoP BLOCK
RX
HDLC
RX
RAW