Owner's manual

Version 2.3

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 Tab l e 4. Refer also to "HMI Definitions" on page 33 and "HMI Access Code" on

page 34.

Table 4. HMI messages

Message

DRQ Handshake

Mode

A B C D

Translate Address n/c Address (MS) Address Address (LS) 0xB3

Acknowledge Interrupt n/c n/c n/c n/c 0xB4

Identify read n/c n/c 7 0xB5

Goto Packet Transmit

Buffer

write n/c n/c 6 0xB5

Goto Translation write n/c n/c 5 0xB5

Acknowledge Packet

Receipt

n/c n/c n/c 4 0xB5

Transmit Packet n/c n/c n/c 3 0xB5

Goto Counters read n/c n/c 2 0xB5

Goto Packet Receive

Buffer

read n/c n/c 1 0xB5

Goto Translation read n/c n/c 0 0xB5