RIM 1802G, Руководство интегратора

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Radio interface pins
Integrator Guide 55
16 ~RTS ~Request To Send
This line is an input to the radio modem. The active, request to send, state of this line is low.
This line should be asserted low by the computing device to indicate that it is ready to receive
data from the radio modem. This is a flow control mechanism that is normally handled by the
UART in your serial communication system. If you do not connect this line to your UART, it
must be tied low so that it is permanently asserted and enables communication.
If your device buffer overflows, it should set RTS inactive to signal the radio modem to pause
sending data. There might be a 16-byte overrun after the RTS line is made inactive, so your
device should set RTS inactive at least 16 bytes before any critical buffer overflows.
17 ~DSR ~Data Set Ready
This line is a digital output from the radio modem.
The active, data set ready (DSR), state of this line is low. Your computing device can use DSR
as a confirmation that the radio modem knows the state of the terminal.
18 GND Ground
This line should be tied to the system ground of the host unit. Pin 9 should also be connected
to ground.
19 ~DTR ~Data Terminal Ready
This line is a digital input to the radio.
The active, data terminal ready (DTR), state of this line is low, and indicates that the computing
device is ready to receive data from the radio modem. De-asserting this line high turns
communication off; the radio modem does not attempt to deliver data to the computing
device until ~DTR is again asserted low. Deasserting ~DTR also reduces power consumption
significantly even with the radio on.
If you do not intend to use ~DTR, tie it to ground so that it is always asserted during radio
modem operation.
This line should be deasserted when the radio modem is off. Driving ~DTR low when the radio
modem is off consumes unnecessary power.
Pin Label Description