CS1810XX Datasheet, PDF (28/54 Pages) Cirrus Logic – Digital Audio Networking Processor

CobraNet Hardware User’s Manual
Host Management Interface (HMI)
7.4 Protocol and Messages
The message conduit is used to issue commands to the CS1810xx/CS4961xx and
retrieve HMI status. The data conduit is used to transfer data dependent on the HMI state
as determined by commands issued by the host via the message conduit.
7.4.1 Messages
Messages are used to efficiently invoke action in the CS1810xx/CS4961xx. To send a
message, the host optionally writes to the A, B, and C registers. Writing to the D register
transmits the message to the CS1810xx/CS4961xx. A listing of all HMI messages is
shown in Table 4. Refer also to "HMI Definitions" on page 33 and "HMI Access Code" on
page 34.
Message
Translate Address
Acknowledge Interrupt
Identify
Goto Packet Transmit
Buffer
Goto Translation
Acknowledge Packet
Receipt
Transmit Packet
Goto Counters
Goto Packet Receive
Buffer
Goto Translation
DRQ Handshake
Mode
n/c
n/c
read
write
write
n/c
n/c
read
read
read
A
B
Address (MS)
n/c
n/c
Address
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
n/c
Table 4. HMI messages
C
D
Address (LS)
n/c
7
6
5
4
3
2
1
0
0xB3
0xB4
0xB5
0xB5
0xB5
0xB5
0xB5
0xB5
0xB5
0xB5
28
©Copyright 2005 Cirrus Logic, Inc.
DS651UM23
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