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2019 Radiocrafts AS
RC232 User Manual (ver 2.01)
RC232 USER MANUAL
4 Power Management
There are different ways to minimize the total current consumption and thus extend the battery lifetime for battery
operated devices. What determines the battery lifetime is determined by several factors, for example how often you
send packages. But it is also crucial to be able to set the module in a state where it draws very little current when
you are not sending. It is also important that the low power mode retains settings so that you spend a minimum
time “on” every time you wake up the module to send a packet.
The Radiocrafts modules offer several configuration options to allow the module to be “off” for an extensive part of
the time:
o
SLEEP_MODE = 0x00, using Config-pin and Z-command to control SLEEP mode.
o
SLEEP_MODE = 0x02, using RTS/SLEEP pin to control SLEEP mode.
o
Turn off module completely (not recommended) except for RC12xx.
The details of these methods are described in the following subchapters.
4.1 SLEEP_MODE = 0x00
If SLEEP_MODE = 0x00, you can enter the low current SLEEP mode by sending the Z-command while in config
mode and still keeping the CONFIG pin low. Exit SLEEP by releasing the config pin as shown in the diagram
below.
CONFIG
UART Command
Z
MODE
IDLE
CONFIG
SLEEP
IDLE
Note!
During SLEEP the CONFIG pin does not have any internal pull-up, so the CONFIG pin must be driven high
in order to wake the module. Any activity on the RXD pin will make the module wake up, but immediately return to
Sleep as long as CONFIG is kept low. Such activity on the RXD pin should be avoided in order to reduce current
consumption. All configuration settings and RAM values are retained during SLEEP.
4.2 SLEEP_MODE = 0x02
With SLEEP_MODE = 0x02 you can enter and exit the low current SLEEP mode by pulling the SLEEP pin low like
the diagram below shows. SLEEP_MODE = 0x02 must not be used together with UART flow control.
SLEEP
MODE
IDLE
SLEEP
IDLE
Note!
During Sleep the SLEEP pin does not have any internal pull-up, so the RTS/SLEEP pin must be driven high
in order to wake up the module. Any activity on the RXD or CONFIG pins will not make the module wake up.
Activity on module pin 16 and 17 can wake the module and must be avoided (do not connect). CONFIG must be
