PIC16F628A in Pulse Dial Security System - Help needed

Hi everyone ,,

I am new to the field of micro controllers ..
But somehow i have managed to learn a little from sites about what is a micro controller !!!
Recently i found a project on net viz. " A SECURITY SYSTEM WHICH USES A PIC16F628 AND USES PULSE DIALING SYSTEM ".

the project is given in this site :

**broken link removed**

I have edited the program with my phone number as instructed .

The program is in assembly code. And i have compiled it to hex using mplab.
The problem is that i have bought a PIC16F628A but the circuit features pic16f628.
And moreover the circuit consists of 3V DC relay but i am making use of a 5V dc relay from GOODSKY. So should i take the 33 ohm resister off ??
And the modem transformer i am using is a 150:150 ohm one but in the circuit it consists of a 600:600.

Also i have included the original source for this project from makezine blog.
Please help me whether the resistor values in the circuit are correct.

And finally one more doubt !!!
I have compiled the asm file to hex and resulted to me in 597 bytes.
I have attached the hex file also. Have i compiled it correctly ??

Please guide me to do my first microcontroller project friends.
And i will be really thankful to you all ...

Cheers ,
Kumar...

hi friends ,,,

i have somehow programmed the pic outside!!!

Now all i need to know is how to enter zero in the asm code for the phone number.
Cuz when i enter the number containing a zero and burn the chip the pulse keeps on dialing ...
How should i represent that zero in asm code !!!>>>>???

Please help !!!

Pulse Dialing

Hi

I am not sure if this is what you mean - but to pulse dial '0' you have to send 10 pulses down the line.

Hope this is of some help

when i enter the '0' the pulse count is continuous and non stop ..
as u said it should give only 10 pulses ...
there is no problem with other numbers ..

so i think there is some mistake in the program ..

pls help me with this ..

thanks !!!

rskumar89 said:

when i enter the '0' the pulse count is continuous and non stop ..
as u said it should give only 10 pulses ...
there is no problem with other numbers ..

so i think there is some mistake in the program ..

pls help me with this ..

thanks !!!

Click to expand...

Hi,
Ran your program in Oshonsoft simulator.
When you load '0' from your digit table into counter1, you load the counter1 with zero, then you decrement.!!! so the next counter1 value is 0xFF [255].!!!

There is no mistake, you need to enter zeros as tens. So, change retlw d'0' to retlw d'10'.

Mike.

thanks a lot pommie ...
I will try this and will notify u again !!

Thanks !!

hi friends,,

I have finished building this project and it s working well.
But now i want to extend it so it can take about 5 to 10 phone numbers and dial it when the alarm goes off.
I want it to be programmable by any user with help of a keypad or a telephone in the parallel line without the help of A computer where it programs it again and again.

Pls help friends,,,

Thanks...

Store the numbers in the data EEPROM area, and write all the program parts you need to do the keyboard reading, display, storage and retrieval.

A 16F628 may start to struggle for pins a bit, moving to the slightly larger 16F876 may be an idea.

I suspect you could do it with an 18 pin PIC with one or two pins left over if you use 4-bit LCD interface mode and re-purpose the LCD D4-D7 driver pins as column or row driver lines for the 4x4 switch matrix.

If you do need more pins you might look into the recent 20 pin offerings like the 16F690 which has become quite popular.

Mike