DNT500
2008 by RF Monolithics,
Inc.
22
M-0500-0000 Rev D
Data
= User data (variable size, 0 to 128 bytes).
Addr = MAC address of the sender for a reply or event, or recipient for a command (3 bytes).
TxStatus = Result of last TxData operation (1 byte).
0 = Acknowledgement received.
1 = No acknowledgement received.
2 = (Remote) Not linked.
3 = Recipient holding for flow control.
RSSI = RSSI, range 0x01 to 0xFE. Values 0x00 & 0xFF have special meanings (1 byte).
0x00 = No RSSI measured because no ACK was received.
0xFF = No RSSI measured because packet was relayed.
NwkID = Network identifier of network joined (1 byte).
BaseMacAddr = MAC address of base that the remote joined (3 bytes).
BootSelect = Code indicating whether to do a normal reset or a reset to the bootloader (1 byte).
(0 = normal reset, 1 = reset to bootloader)
AnnStatus = Status announcement (1 byte).
Additional fields are also reported depending on the status code:
Status
code
Add'l fields
A0 = Radio has completed startup initialization.
none
A1 = Base: Network formed, ready for data.
NwkID
A2 = Base: A remote has joined me.
MacAddr (0xFF if none)
A3 = Remote: Joined a network, ready for data.
NwkID, BaseMacAddr, Range
A4 = Remote: Exited network (base is out of range). NwkID
A5 = Remote: Base has restarted.
none
A7 = Base: Remote has left the network.
Addr
Status codes for error conditions
Add'l
fields
E0 = Protocol error -- invalid message type.
none
E1 = Protocol error -- invalid argument.
none
E2 = Protocol error -- general error.
none
E3 = Protocol error -- parser timeout.
none
E4 = Protocol error -- register is read-only.
none
E8 = UART receive buffer overflow.
none
E9 = UART receive overrun.
none
EA = UART framing error.
none
JoinAddr = MAC address of radio joining (3 bytes).
Range = Range measurement of radio joining. (1 byte).
4.1.2 Escape sequence
The escape sequence is a sequence of bytes that the user can input in transparent mode to
switch the radio to configuration mode. In the DNT500, we define the EnterProtocol-
Mode command as the ASCII escape sequence “DNT500” (quotation marks are not part
of the sequence). A radio that is already in protocol mode will respond to this command
the same way as a radio that is in transparent mode. For the escape sequence to be recog-
nized, byte flow must pause at least 20 ms before the escape sequence is sent.
