1, on-board power switch, convenient program debugging and switch operation.
2, high current power supply design using the special power IC–MIC29302, to ensure stable power supply. Why we have not use LM7805? the 5V output voltage very close to the module’s upper critical point, so work long time, poor stability, it’s dangerous, the maximum output current of LM7805 is 1.5A and MIC29302′s maximum output current up to 3A, in poor signal areas, in order to search for network signals, the module will enhance the their transmit power, then the current consumption is very large.
3, on-board hardware resources, abundant interfaces:
Provides NOKIA5110 LCD interface, the screen is widely used, and very cheap.
Buzzer Circuit: 5V buzzer driver.
DS18B20 temperature sensor interface: 1-wire digital temperature sensor interface, only takes a microcontroller I / O port, you can get real-time temperature to complete the multi-point temperature acquisition.
4 * 4 matrix keyboard: user can program custom key functions to achieve the key control. Used to make a phone dialing system.
1 relay interface: for users to send SMS or call phone to control the relay , relay’s load in case of 220V AC, 3A current.
4, 4-LED status indicators: the user can control LED to facilitate the debugging work.
5, three kinds of communication jump :
a) PC – EM310 communication
b) PC – MCU communication: MCU can download a program through a serial port , without additional programmer.
c) EM310 – MCU communication.
6, All MCU I / O pin expansion : 40 pin outside , for users extended use in the each side of the MCU pins, all directly connected with the chip .
7, on-board microphone, handset interface: users can connect with the microphone and speak on the board.
8, STC89Cxx, the highest frequency of 90 MHz, within 4 K of FLASH memory, the program more than 8 K or so in EEROM, 512 of B-1208 B within 36 of RAM, IO mouth.
9, 1 LED indicator light: a power instructions.
10, ISP interface (used for program download, serial ports surveillance).
11, RS232 interface ISP; Support a serial port debug.
12, 9 v dc power input: take the power indicator.