Lexicon DC-2 - Manual (Page 5)

Lexicon, Inc.
DC-2/MC-1 Serial Communications Protocol
Printed on: 10/19/00
5 of 44
The DC-2/MC-1 uses simple notification, command, response and acknowledgment packets to have
communication transactions with a given HOST. This protocol is designed for point to point
communication between a HOST and DC-2/MC-1. The DC-2/MC-1 Protocol is a 3 layered system. The
DC-2/MC-1 serial protocol allows for the DC-2/MC-1, or the HOST to initiate a communication
transaction. Most transactions are initiated by the HOST. DC-2/MC-1 then responds to the HOST
command with either a response or acknowledgment packet. There are a few asynchronous notifications
that DC-2/MC-1 initiates indicating system changes. Each transaction initiated must wait for a
corresponding response before initiating the next transmission.
The 3 protocol layers are: Physical, Data Link, and Application Layers.
5 Physical Layer
5.1 DB-9 RS232 Connector
Dc-2/MC-1 Typical Host
Ch A Transmit Data 2 2 Rx Data
Ch A Receive Data 3 3 Tx Data
Ch A Ground 5 5 Ground
9 Pin D-Shell
(female) lower
connector 9-Pin D-Shell
(male)
Note: The wiring requirements for a 9 pin to 9 pin serial connection, are a male to female straight through
cable.
5.2 Serial Port Driver
DC-2/MC-1 serial port has been setup to operate as follows:
Operating Mode: Full Duplex
Baud rate: 19.2K baud
Data Size: 8 bits
Parity: Odd
Stop Bits: 1
Physical Layer (RS232)
Data Link Layer
Application Layer