Say this... - cheap voice control

Instead of expensive and difficult to buy systems for voice control, a simple mobile phone was used in this device. Kay components of the voice control is Atmega8 and Sony Ericsson K700. The main advantage of K700 in this case is the possibility of voice dialling, and so called 'magic word'. Those functions were used as 'voice transmitter'.
Sony Ericsson was connected with the speaker-phone and uP from RS232 (communicating with it was done by AT commands).
uP checks whether the mobile phone isn't making a call at the moment. If it is, the uP checks to which number the phone is calling, disconnects the call and depending on the number, switches the status of a particular pin. The particular number is dialled using a voice command by the phone.
The whole was mounted on Tesla plate ZL2AVR and the speaker-phone. In the upper right corner it is connected to the uP and 5 LEDs, whose status is changed every time the phone receives an appropriate voice password.
The whole was made only for tests, that is why it has no housing and cables are outside.
The mobile phone wasn't changed at all, so when it is plugged off, it can still work as a phone.
To work, the 'magic word' has to be activated in the phone, preferably an unheard in everyday life (like abracadabra), then you need to add five contacts with numbers *111, *222, *333, *444, *555 and sign them by appropriate voice commands (first, second etc.). Of course, 'magic word' and control commands may be changed to more appropriate (like light, television, etc.). So prepared phone can be then attached to the system and run the whole.
As you know, the system that recognizes the voice is not perfect and sometimes it makes mistakes. Then it recognizes another word as 'magic word'. When this happens, the system doesn't wait for another command (control command) and if it doesn't get another command or it gets an unclear word, it wouldn't react.
The system has its advantages:

• it is not expensive to make (allows to use a broken phone, eg. with dead LCD)
• simple construction
• can be used in many devices

and unfortunately, disadvantages:

• the phone must have active card and has to catch radius (although the account may be zero)
• when the command is wrong, you need to wait until the phone goes to the main menu
• reaction to the change of status after termination of the password takes about 1-2 seconds

Below there is a video. Pay attention to upper right corner of the plate – LEDs change status accordingly to the commands:


Link to original thread (code in attachment) – Powiedz to... Czyli tanie sterowanie głosem (vol. 2)