Operating Modes - SIM Tech SIMCom SIM900-DS Hardware Design

Table 2: Coding schemes and maximum net data rates over air interface
Coding scheme
CS-1
CS-2
CS-3
CS-4
2.2

Operating Modes

The table below summarizes the various operating modes of SIM900-DS.
Table 3: Overview of operating modes
Mode Function
GSM/GPRS
SLEEP
GSM
IDLE
Normal
GSM
operation
TALK
GPRS
STANDBY
GPRS
DATA
Normal power down by sending the AT command "AT+CPOWD=1" or using the PWRKEY.
The power management unit shuts down the power supply for the baseband part of the
Power down
module, and only the power supply for the RTC is remained. Software is not active. The
serial port is not accessible. Power supply (connected to VBAT) remains applied.
AT command "AT+CFUN" can be used to set the module to a minimum functionality mode
Minimum without removing the power supply. In this mode, the RF part of the module will not work or
functionality the SIM card will not be accessible, or both RF part and SIM card will be closed, and the
mode serial port is still accessible. The power consumption in this mode is lower than normal
mode.
SIM900-DS_Hardware Design_V1.00
1 timeslot 2 timeslot
9.05kbps 18.1kbps
13.4kbps 26.8kbps
15.6kbps 31.2kbps
21.4kbps 42.8kbps
Module will automatically go into sleep mode if the conditions of sleep
mode are enabling and there is no on air and no hardware interrupt (such as
GPIO interrupt or data on serial port).
In this case, the current consumption of module will reduce to the minimal
level.
In sleep mode, the module can still receive paging message and SMS.
Software is active. Module registered to the GSM network, and the module
is ready to communicate.
Connection between two subscribers is in progress. In this case, the power
consumption depends on network settings such as DTX off/on,
FR/EFR/HR, hopping sequences, antenna.
Module is ready for GPRS data transfer, but no data is currently sent or
received. In this case, power consumption depends on network settings and
GPRS configuration.
There is GPRS data transfer (PPP or TCP or UDP) in progress. In this case,
power consumption is related with network settings (e.g. power control
level); uplink/downlink data rates and GPRS configuration (e.g. used
multi-slot settings).
Smart Machine Smart Decision
4 timeslot
36.2kbps
53.6kbps
62.4kbps
85.6kbps
10
2013-01-20