Tag Archives: GSM/GPRS MODULE

MADUINO ZERO SIM808

#48 MADUINO ZERO SIM808 GPS TRACKER

The Maduino Zero SIM808 GPS Tracker is an IOT (Internet of things) Solution based on the 32-bit Atmel’s SAMD21 MCU and GPRS/GSM GPS module SIM808. It intergrates a micro Controller ATSAMD21G18, GRRS/GSM module SIM808, which is the upgrade version of SIM900, power management and storage, to make the SIM808 GPS Tracker ready for IOT projects such as smart-home, outdoor monitoring, shared bicycle, etc. The Marduino Zero SIM808 GPS Tracker based on the Arduino, users can program it with Arduino IDE, which is very easy especially for the none-programmers.

This is the V3.4 version, Note that to ensure the module starts up right, a lipo battery is needed to power up the Maduino Zero SIM808 GPS tracker V3.4.

Quick Spec

  • AT Input Voltage: 3.4-4.2V
  • Microcontroller: ATSAMD21G18, 32-Bit ARM Cortex M0+
  • Clock Speed: 48 MHz
  • Micro SIM connector
  • Integrated Power Control System
  • AT command interface with “auto baud” detection Quad-band: 850/900/1800/1900Mz
  • Send and receive GPRS data (TCP/IP, HTTP, etc.)
  • GPS L1 C/A code
  • 22 tracking /66 acquisition channels
  • Tracking: -165 dBm
  • Cold starts: -148 dBm
  • Time-To-First-Fix:Cold starts-32s (typ.), Hot starts-1s (typ.),Warm starts-5s (typ.)
  • Accuracy: approx. 2.5 meters
  • Interface: I2C/SPI/UART/18*GPIO
  • Arduino compatible
  • Working Temperature: -40 – 85℃
  • Size: 40 x 55mm
  • Net Weight: 23g

PRO MINI FARM ALARM V1.0

#42 PRO MINI FARM ALARM V1.0 BREADBOARD

The Pro Mini V1.0 testing for the Farm Alarm

The Pro Mini has proven to be a suitable solution. The board is very small and has more than enough specs to control the GSM/GPRS module while also sending data to a remote server via TCP.

The Pro Mini requires an FTDI programmer since there is no USB port on the board.

FTDI programmers pin out relative to the Pro Mini
Pro Mini ( ATMEL MEGA328P MU1039 )

FAILED ATTINY85 EXAMPLE

#41 A FAILED ATTINY85 EXAMPLE (GSM/GPRS)

A quick solder up to test the circuit (had issues with power sharing between GSM module and ATTINY85)

My first attempt to build a small circuit which controls a relay to an alarm speaker was a failure. Contrary to popular belief failure in electronics projects is quite common and I would argue that it is of paramount need if you want to learn anything.

Surprisingly my failure was in using the ATTINY85 instead a Pro Mini, Uno or Mega. Some problems I had were:

  • Not enough RAM to hold all my variables (I had to scrounge 😢)
  • Very limited FLASH memory.
  • GSM module interferes with the ATTINY’s 5v power source when connected using the same source with no filtering.

In a later project I created a reliably working solution with the Pro Mini as the brains.

My goal was to create a small circuit which uses the ATTINY85 as the brains. It uses the A6-GSM-Module to receive SMS’s, phone calls and sends TCP data. Finally it has a 5v relay which will switch on/off an alarm speaker. The theory is that when I’m on the farm in the fields and not near the house, I have the option of remotely starting an audio alarm at will. This should be a deterrent to potential criminals.

I made an easier to debug testing circuit with exposed copper traces (Same issues)

After making an easier to debug circuit I tried to get the ATTINY85 to work happily with the GSM module. This was going to be a bit complicated and I suspect I would have to isolate power between the ATTINY85 and the GSM module. This would require more components and the board is already looking cramped. A much easier solution is to use the Pro Mini instead of the ATTINY85.

The Pro Mini is most certainly a beauty.