Murata Electronics North America DNT500FP Manuale Utente
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©2008 by RF Monolithics, Inc.
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DNT900 - 11/05/08
RSSI = 2’s complement value in dBm, with a range of -128 (0x80) to +125 (0x7D) dBm (1 byte);
large positive RSSI values will not occur under ordinary circumstances. RSSI values 126 (0x7E)
and 127 (0x7F) have special meaning:
large positive RSSI values will not occur under ordinary circumstances. RSSI values 126 (0x7E)
and 127 (0x7F) have special meaning:
0x7F = No RSSI measured because no ACK was received
0x7E = reserved for future use
0x7E = reserved for future use
NwkID = Network identifier of network joined (1 byte).
BaseMacAddr = MAC address of base that the remote joined (3 bytes).
AnnStatus = Status announcement (1 byte). Additional fields are also reported
depending on the status code:
BaseMacAddr = MAC address of base that the remote joined (3 bytes).
AnnStatus = Status announcement (1 byte). Additional fields are also reported
depending on the status code:
Status code
Additional fields
A0 = Radio has completed startup initialization
none
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
A7 = Base: remote has left the network.
Addr
Status codes for error conditions
Additional 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
Range = Range measurement of radio joining. (1 byte).
BootSelect = Code indicating whether to do a normal reset or a reset to the bootloader (1 byte)
BootSelect = Code indicating whether to do a normal reset or a reset to the bootloader (1 byte)
(0 = normal reset, 1 = reset to bootloader, 2 = activate OTA bootloader)
4.1.3 Escape Sequence
The escape sequence is a series of bytes that the user can input in transparent mode to switch the radio
to configuration mode. In the DNT500, we define the EnterProtocolMode 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 recognized, byte flow must pause at least 20 ms before the escape sequence is sent.
to configuration mode. In the DNT500, we define the EnterProtocolMode 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 recognized, byte flow must pause at least 20 ms before the escape sequence is sent.
4.1.4 CFG Select Pin
A falling edge on the CFG pin is the equivalent of entering the escape sequence to invoke the protocol
mode. A rising edge on the CFG pin is the equivalent to sending the exit protocol command. The input to
the CFG pin is de-bounced to make it compatible with a mechanical switch or jumper.
mode. A rising edge on the CFG pin is the equivalent to sending the exit protocol command. The input to
the CFG pin is de-bounced to make it compatible with a mechanical switch or jumper.
4.1.5 Flow Control
There are two flow control signals between the radio and the host, RTS and CTS. See Section 2.9 for
flow control details.
flow control details.