Kele • RUT-G Manual 2005 • www.kele.com • USA 888-397-5353 • International 901-382-6084
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RS232/485 INTERFACE KEY
Points
are the field device data (value) termination or origination. They can be analog or digital.
Point Number
can be 1 through 4 depending on type of Frontier field device. It identifies the Frontier field device’s
targeted (addressed) data point. Some devices have only one or two points. This value is part of the addressing used
by the Frontier radios.
Polled
is a condition set in the Global Configuration Packet and affects only RS232 output data transmitted from the
network interface key to the user device. For RS485 operation, polling is automatic as it is the only way the user’s
device will get data from the network interface key.
When set to 0, this flag instructs the network interface key to send the output value any time a Frontier field trans-
mitter update occurs in the Gateway. If set to 1, the network interface key output value will be transmitted only when
requested by the user device "Network Request Update Data Packet" (data type 7).
RF Radio Transceiver
is the RF radio that transmits and receives data to and from the Frontier field devices.
RTS
is the handshake pin to the user device RS232 port. The network interface key sets this to a high state when the
network interface key is ready to transmit to the user device. After the transmission is completed, the RTS will return
to a low state. Refer to Figure 2 and Figure 3.
RXD
is RS232/485 received data by the user’s device and Frontier Gateway network interface key.
Signal Strength
is sent to the user device in the output data packet. This value, in db, is the power of the Frontier
transmitter signal transmitting to the Gateway. Typically the closer the Frontier transmitter is to the Gateway, the great-
er the signal strength. It will always be higher than the SNR. Typical values are 25 db and above.
Signal-to-Noise Ratio (SNR)
is sent to the user device in the output data packet (data type 5). The SNR is the quality
of the signal based on the signal strength and the surrounding RF noise received by the network interface key from
a Frontier transmitter. It is a db measurement. A good SNR is 18 db and above.
Start Character
is the '<' (hex 0x3c) character and is always the first byte in all packets. If for some reason a '<' (hex
0x3c) character is received before the End Character ('\r' hex 0x0d) of the previous message, the previous message
is discarded. The Start Character is a constant, not a data item.
Time Interval
(in seconds) for Output Configuration Packet is the means in which the network interface key deter-
mines a loss of signal from a Frontier transmitter. If a transmission from a Frontier transmitter has not been received
within the time period, the loss of signal diagnostic bit will be set. Maximum time interval for Input Configuration Pack-
ets is used by the network interface key to force a transmission to a Frontier field receiver. If the user device has not
made an update to the network interface key within this time period, the network interface key will resend its last value
to the Frontier field device.
DEFINITIONS (CONTINUED)
