Concept: We are using SMS service to control upto 10 electrical/electronics devices remotely. The SMS service has no range limitations so we can control devices from any distance where network is available.
Here we are using a GSM module/GSM telephone as a receiver for our remote control, a 8051 architecture micro-controller to read sms from GSM module. The 8051 manipulates on data fetched from GSM in terms of sms and takes required action. We are connecting upto 10 relays to i/o of the micro-controller. By connecting relays we can switch ON-OFF the devices.
Implementation: In this project we are going to use AT89S52 microcontroller ic.
AT89S52 is a isp ic, the benefit of in service programming ic is you do not require a different burning kit for this. Please refer AT89S52 data sheet for further information on isp. http://www.ziddu.com/download/6426941/AT89S52datasheet.pdf.html
Normally the sony ericsson phones uses PDU procol for SMS, & nokia uses FBUS protocol for transferring sms. So on basis of these two protocol we have to program our microcontroller to decode it.
We used sony ericssons PDU protocol in our project.
For more information on PDU protocol got to http://www.dreamfabric.com/sms/
To manipulate phone transreciever there are AT commands, this is a set of attention commands.
Download sonyericsson AT command guide here http://www.ziddu.com/download/6427178/dg_at_2006--09_r13a.pdf.html
Connect Rx/Tx of phone to i/o of the microcontroller, configure this ports as input.
Then decode PDU format to know which device to switch.
We can use PDU format effectively by allowing only on mobile number to switch the devices, by checking number with if condition in our microcontroller program.
For Schematic, Parts & kit information contact me.