connection betweem MicroController( pic 16f877a) & mobil

[jade]

hello plz help me to solve a this problem :
i want to connect microcontroller with mobile(nokia) to make communication between them & ididn't have information enough because i didn't know what is the role of max 232 exactly

 

[BeeBop]

Re: connection betweem MicroController( pic 16f877a) & m

Hi Jade,
The max 232 is a level converter. A micro doesn't output a negative voltage, and the voltage rails of most micros are less than 5 volts. RS232, on the other hand, uses a voltage swing of +12 - 15 volts to -12 - 15 volts. The max increases the voltage put out by the microcontroller to a level which can be read by an rs232 device (like a PC, or in your case, a phone.) The max 232 chip uses electrolytic caps, but there are versions of the chip which work with standard 'mono' 104 caps, as well as the max233, which needs no external capacitors. You can also realize such voltage shifter with individual components, but with the max so easy to use, why not go with it?
The max chips are available in surface mount, if you want to keep your circuit board size small.
I hope this helps you, and if you have any further questions, just ask, and I'll try to answer.
Best wishes,
Robert

 

[rchinthaka]

Re: connection betweem MicroController( pic 16f877a) & m

max232 is only doing voltage convertion, but it not enough to connect the mobile phone to 16f877, you have to follow the protocol of the nokia known as FBUS which is useing to communicate with pc or eny other external device. you can find lot of importtant information about FBUS using following link try it!!!

**broken link removed**

i did what you want to do is using information got from this site!! it is working properly!!!

 

[ashish sharma]

can u give the details of your project

 

[rchinthaka]

Re: connection betweem MicroController( pic 16f877a) & m

hi,

i did both way communication link to my PIC using SMS, on my project i read sms and reply them from my program, on the reply i did some controlling of home appliences using a SMS as well. i used nokia 3310 phone, dont try to make the data cable yourself, just buy it, for 3310 data cable will be only US$10, it will minimize your errors.