Phonetics Sensaphone SCADA 3000, Руководство пользователя

Страница: 118 / 336

Figure 3: Transmit Data Logic Diagram
Figure 4: Receive Data Logic Diagram
The following definitions describe the timing parameters.
RTS Hold delay: RTS stands for request-to-send. This hardware signal tells the
radio modem that we wish to transmit data. The RTS signal remains raised until
all of the data has been sent. The RTS Hold delay is the amount of time that the
RTS signal remains raised after the data has been sent. Typically this must be set
to between 10-50ms, but to ensure reliable data transmission, you should check
your radio modem specifications for this parameter.
CTS Timeout: CTS stands for clear-to-send. The radio modem will raise CTS
when it is ready to transmit data. The CTS timeout is the amount of time the
SCADA 3000 software will wait for CTS to be returned from the radio modem
before it gives up.
DCD Time Out (Transmit): DCD stands for data-carrier-detect. The DCD signal
indicates that the radio modem is receiving a carrier signal from another radio
modem. The DCD transmit timeout is how long the software waits for DCD to
drop before raising RTS when transmitting.
DCD Time Out (Receive): DCD receive timeout is how long the software waits for
DCD to drop before it stops waiting for a packet to be received.
Flush Buffers after sending packet: Flush Buffers clears the send and receive buffers
immediately after sending a packet. It can eliminate some noise but is not always
necessary.
The following figure shows an illustration of how a typical radio network might look:
12-4
SCADA 3000 User’s Manual