AudioNav EF
Config Utility & API
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1400 Series AudioNav EF - Config Utility & API Rev 1.2
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AudioNav Device Communications
AudioNav
keypad
uses the ASCII/binary Message format described below. Every message that is sent from a host
should be acknowledged with the control byte ACK (0x06). A retransmission should be initiated if an NAK (0x15) is
received or if no acknowledge is received at all.
Message Formats
A Alpha character, 'A'-'Z' and 'a' - 'z'
C Control character one byte in length.
H Hexadecimal characters, ‘0’-‘9’, ‘A’-‘F’
N Numeric character, ‘0’-‘9’
S Special characters, entire character set 0x00 - 0xFF
ASCII Message Format
Message Field
Type Length Description
1 STX
C
1
Control character Start of Text = 0x02
2 Message Id
H
2
Defines the type of message and format of the data field
3 Data Length
H
2
Hexadecimal value represented in ASCII defines the
number of bytes in the data field. '00' to 'FF'. Maximum
data field size is 256 bytes.
4 Data Field
S
var
In binary format
5 ETX
C
1
Control character ETX = 0x03
6 LRC
C
1
Longitudinal Redundancy Check Digit, calculated on all
previous data including STX
