Datasheet

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Channel Address Logical Channel
0x007E 63
0x01FE 0
(1)
Note: 1. Logical Channel 0 is the System Channel and is reserved.
48.6.3.2 Host Bus Interface Block
The Host Bus Interface (HBI) block provides a 16-bit parallel slave port that provides an external Host Controller (HC)
with access to all MOST channels and data types.
Up to 64 independent HBI channels are available to the HC, each configurable for either transmitting or receiving a
particular application data type (synchronous, isochronous, asynchronous, or control). The HBI block provides source
and sink access to the full network data bandwidth.
HBI Physical Addresses
T
o access a particular HBI DMA channel, hardware must first translate the HBI channel address to a channel
allocation table (CAT) physical address. This physical address is then used to retrieve the channel label (CL), which
in turn retrieves the channel descriptor.
See the following table for more information on the mapping between the HBI channel address and physical address.
Table 48-9. HBI Channel Address to Physical Address Mapping
HBI Channel CAT Address CAT Offset
0x0 0x88 000
0x1 0x88 001
0x2 0x88 010
0x3 0x88 011
0x4 0x88 100
0x5 0x88 101
0x6 0x88 110
0x7 0x88 111
0x8 0x89 000
... ... ...
0x3E 0x8F 110
0x3F 0x8F 111
48.6.3.3 Routing Fabric Block
The Routing Fabric (RF) block manages the flow of data between the MediaLB Port and the HBI Port. Bus
multiplexers and a bus arbiter are implemented in the RF block for accessing the channel table RAM (CTR) and data
buf
fer RAM (DBR).
Each DMA controller in the routing fabric uses Channel Descriptors (stored in the CTR) to manage access to
dynamic buffers in the DBR.
Data Buffer RAM
The MLB has an external data buffer RAM (DBR) that is 8-bit x 16k entries deep. The DBR provides dynamic circular
buffering between the transmit and receive devices.
The size and location of each data buffer is defined by software in the channel descriptor table (CDT), which is
located in the CTR.
SAM E70/S70/V70/V71 Family
Media Local Bus (MLB)
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2019 Microchip Technology Inc.
Datasheet
DS60001527D-page 1349