Sim800 hardware design v1.05

Smart Machine Smart Decision
SIM800_Hardware Design_V1.05 12 2014-03-25
Table 2: Coding schemes and maximum net data rates over air interface
Coding scheme 1 timeslot 2 timeslot 4 timeslot
CS-1 9.05kbps 18.1kbps 36.2kbps
CS-2 13.4kbps 26.8kbps 53.6kbps
CS-3 15.6kbps 31.2kbps 62.4kbps
CS-4 21.4kbps 42.8kbps 85.6kbps
2.2. Operating Modes
The table below summarizes the various operating modes of SIM800.
Table 3: Overview of operating modes
Mode Function
GSM/GPRS
SLEEP
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.
GSM
IDLE
Software is active. Module registered to the GSM network, and the
module is ready to communicate.
GSM
TALK
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.
GPRS
STANDBY
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.
Normal
operation
GPRS
DATA
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).
Power down
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 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.
Minimum
functionality
mode
AT command “AT+CFUN” can be used to set the module to a minimum functionality
mode without removing the power supply. In this mode, the RF part of the module will not
work or the SIM card will not be accessible, or both RF part and SIM card will be closed,
and the serial port is still accessible. The power consumption in this mode is lower than
normal mode.