Brand: other/ other modules are available globally for 4-frequency modules. Sim900 module is fully compatible with sim900a. The difference is that sim900a is a dual frequency module, which can not be used in some countries. Sim900 module is universal in the world!

The power supply requirements of this module: 5V power supply, and USB power supply of computer can meet the requirements in the initial stage of computer debugging. Because we added a large capacitance of 1000uf. DC with a large amount of power consumption recommended for long-time transmission data is recommended for DC with a voltage of more than 1a. TTL level serial port is adaptive compatible with 3.3V and 5V single chip microcomputer.

Video tutorial:http://pan.baidu.com/s/1dDGSVr7

Full set of information links:http://pan.baidu.com/s/1lQSRs

Procedures provided:

1、 Brief introduction of sim900 module

此模块供电要求：5VThis module power supply requirements: 5V power supply, computer debugging initial computer USB power supply can meet the requirements. Because we added 1000uf of large capacitance. The power consumption of long-time data transmission is large. It is recommended to use DC above 1a. The TTL level serial port is adaptive compatible with 3.3V and 5V single chip microcomputer. It can be directly connected to MCU. Standby at about 80mA, you can set the sleep state at about 10mA, low power consumption. Computer debugging USB -- 232 and USB -- TTL can be, depending on the accessories. Support SMS, data, MMS, Internet, etc. Reset needle lead out, can realize unattended remote reset, with DTMF function to realize remote control function. The biggest advantage of the module is to retain 232 ports, which can monitor the execution of 51 low-end MCU and module instructions during learning or development, and find out the reasons faster, saving the time of development and learning.
In addition, the sim900 module has DC power supply above 3.5 -- 4.5v1.5a, which is suitable for 3.7V lithium battery power supply. Need to contact customer service. TTL level of this module is compatible with 3.3V system, 5vttl system needs to pass 232 control module.

Advantages of this module:

Serial port circuit: TVs and magnetic bead protection device are used to protect the board from surge and high voltage.

• SIM card circuit: add smf05c electrostatic discharge chip.
  Antenna circuit: short and straight to ensure signal strength.
  PCB display: each interface is marked by screen printing, which is convenient for secondary development. The design completely follows the sim900 hardware design manual.
  A 5V power supply interface: we have done protection, even if the connection is reversed, it will not burn the board. At the beginning of the computer debugging, USB power supply is enough; The power consumption for long-time data transmission is large. We recommend DC power above 1a.
  One TTL interface: support 3.3V MCU and 5V MCU. That is to say, it supports 51 kinds of 5V MCU and STM32 MCU.
  Two way antenna interface: SMA antenna interface, IPX Mini antenna interface (default no welding).
  One way 232 level interface: that is to say, you can directly connect the module to the computer through a 232 --- USB serial port cable. You can also connect the computer with USB -- TTL, depending on your accessories. There is no need to spend more money to buy accessories, which is the biggest difference with other sellers.

Detailed introduction of sim900 module:

Computer control module method:

In one word, it is to control the module by issuing instructions (at instructions) through serial ports. The following describes two common ways to control sim900 modules:
The first one: through CP2102 USB transfer to TTL module, our store has sales, computer debugging sim900 module
The second type: connect the module with the computer through Usb-232 serial port cable, and then connect to 5V power supply

• Default shipping list
• Sim900 module * 1
• GSM module antenna * 1
• Module power line * 1,