Operating instructions

76 1892 1335 - Orion Radio Modem Operating Instructions - v2.9 / Aug 2009
Message Syntax
04 = Prefix byte marking start of all messages
IDS = A byte containing the ID number 0-254 of the source in binary
IDD = A byte containing the ID number 0-254 of the source in binary
Note that Base station will always be ID = 0
aa = 1 byte data (a can be any letter)
aaaa = 2 byte data (a can be any letter)
CH = CHECKSUM: additive sum of bytes in message where CH is the
low order byte of the sum of all the bytes in the message, apart
from the first three. I.e. for an 04 IDS IDH 20 message, CH = the
sum of 20.
After a set command is sent, the unit will reply with a confirmation message. All I/O
configuration will be stored in EEPROM until an AT&W command is issued (serial port), or
‘store config’ over-air message (04 IDS IDD 27 CH) is received, when it will transfer it to non-
volatile storage.
Numbers are given in decimal form unless explicitly stated.