Cervis MRF450, User Manual

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Module RF450
U077.0.2-MRF450 10
8.0 Messages
The heart of the communication packet structure is the message field. This field carries the
specific information of the packet. The first byte of the message field is interpreted as the
message ID. The remaining bytes in the message are interpreted based on the message ID.
The message IDs and structures follow.
Table 5. Message IDs and Structures
0 .. n
ID ID-Dependent
Message Field
8.1 Get / Set Parameter
This group of messages is used to set and read module parameters. The first two bytes identify
the specific parameter to be accessed. If data follows the parameter ID, the parameter is set.
The module always replies with the current value of the parameter, or an error code. Each
parameter can vary in data length. See the table of Parameter ID assignment and data lengths
for specific values.
Table 6. Parameter ID Assignment and Data Lengths
Get / Set ID = 0x00, Reply = 0x90.
0 1 2 3 .. n
ID Parameter ID Parameter Value
0x00 Optional. Set if present
The following table describes the available configurable parameters.
Table 7. Configurable Parameters
ID Parameter Bytes Default Description
0x0000 Channel 2 0x0000 Sets the operating center frequency. (Channel
* 1000). Values above 20,000 are coerced to 20,000.
NOTE: module will NOT transmit until this parameter is
set – even if the desired channel is 0.
0x0001 Power 1 0x00 Sets the output RF power. 0 – 255, logarithmic scale. 255
is no greater than module maximum (see ID 0x0050)
0x0002 LED EN 1 0x0F Bitwise LED enable. A set bit permits LED operation. Bit
0 enables LED0, etc.
0x0003 Baud 4 115200 Sets the baud of the host interface when in UART mode.
0x0004 Pin Mode 1 0x00 Binary-encoded options
1 If clear F0 active low (low when message waiting)
2 If clear F1 active low (high when CTS)
0x0010 My PAN 2 0x0000 Sets the PAN ID of the module.
0x0011 My Address 2 0x0000 Sets the address of the module.
0x0018 DST PAN 2 0x0000 Sets the destination PAN ID for the next transmission.
0x0019 DST
Address
2 0x0001 Sets the destination address for the next transmission.
0xFFFF is a broadcast address.
0x0020 Default 1 0x00 0x00 = Idle. Lower power consumption.