
8201, 8202, 8203, 8204 Acceleration Processor Data Sheet, DS-0157-05
Page 115
Exar Confidential
5.3 Channel Manager
There are two channel managers in the 820x. Each channel manager controls one Data
Processing Channel. The DMA controller issues the read and write requests needed to
execute a command and the control the data flow for the Data Processing Channels encode
and decode operations.
5.3.1
Channel Manager Inbound Data Controller
The Inbound Data Controller (IDC) controls the command structure and fetching the source
data. The main functions of the Inbound Data Controller are:
Issue command structure read requests and put the command into the command
buffer after the command completes
Issue source descriptor read requests
Issue source data read requests while maintaining the source data read request tags
and ensuring the source buffer is available before issuing the source data read
request (The IDC can generate a maximum 8 outstanding data read requests)
Issue free pool descriptor read requests if the destination descriptors are all
consumed
Figure 5-2. Channel Manager Block Diagram