RIM 1802G, Integrator Manual

Page: 57 / 76

Turning on and turning off the radio
Integrator Guide 57
Turning on and turning off the radio
To determine the current state of the radio, observe the ONI line. If ONI is high, the radio is on or is
in the process of turning off. If ONI is low, the radio is off or in the process of turning on. The
TURNON pin is a digital signal that turns the radio on and off. It eliminates the need for a power
switch across the power supply to the radio.
Turning on the radio
You can turn on the radio modem on by setting TURNON to high.
During the radio modem’s startup procedure, which can take several seconds, all changes to
TURNON are ignored by the operating system. If the radio fails to respond to a high TURNON line,
the radio might require service or the power supplied to the radio might be too low for proper
operation.
Do not use TURNON to indicate radio status. ONI must be used as the indicator of the radio status.
It is possible for the radio to be off even though TURNON is asserted. In this case, you can turn on
the radio by setting TURNON low and then high again.
Turning off the radio
The RIM 1902G or RIM 1802G requires a controlled shutdown. You can turn the radio modem off by
de-asserting
TURNON .
Data that has been received by the radio modem from the network, but has not been transferred to
the computing device, is not saved. The data is discarded when the radio modem turns off.
When the radio modem turns off, which can take several seconds, all changes to
TURNON
are ignored
by the operating system. To make sure that power consumption is reduced to the lowest possible
levels and sleep mode is achieved, all inputs to the radio should be inactive when the radio is turned
off. In particular, pin 19 (~DTR) should be inactive (3V).
Do not use the
TURNON
state to indicate radio status.
ONI
must be used to indicate radio status. It is
possible for the radio to be on even though TURNON is de-asserted. In this case, you can turn off the
radio by setting
TURNON
high and then low again.
If the application is very power constrained, you only need to remove power from pins 7 and 8.