User's Manual

DR-915 OEM DATA RADIO MODULE
___________________________________________________________________________________________
Revision A INTEGRATOR’S
GUIDE
20
DR-915 DATA RADIO
IN-SYSTEM CONFIGURATION
The DR-915 may be reconfigured while in a host system. This allows the users system
to change the source or destination address and group codes on-the-fly, adding great
versatility to the Ack-Back delivery mode.
General Structure
The general structure of the protocol for programming the DR915L/LT radios is as
follows:
[0xAA] [command] [checksum] [0x55]
where command consists of byte #1, byte #2, byte #3, ..., byte #n as defined below,
and
where the checksum is an 8-bit checksum (a simple unsigned 8-bit addition of bytes)
of data bytes 1 thru n, 0x55, and
where the checksum does not include the beginning 0xAA, itself, or the ending 0x55.
Numbers preceded by “0x” are hexadecimal. All others are decimal.
The DTR pin must be raised prior to sending any commands to the radio. Once a
complete command has been sent to the radio, the DTR pin should be immediately
lowered. If a read command of some sort was issued, the device should be ready to
receive the information immediately. If a Write Command was issued, the device must
allow 250 milliseconds for the radio to reboot itself with the new values before any
other commands can be issued.
As bytes are sent to the radio, each byte will be immediately echoed back to the sender
for confirmation that the radio received the byte.
When any data is being read from the radio, the device should simply read in the data
without echoing the bytes back to the radio.
Command Structure
The format of the data bytes for sending a command to the radios is as follows: