Arduino Pro Mini 3.3V version serial monitor not working

Development Tools IDE 1.x
1

I just got my new 3.3V Arduino Pro mini and uploaded the blink sketch and it worked just fine. I am using the FTDI board from spark fun to program my arduino.

But the problem is when I tried using the example "AnalogSerialRead" I found that my Arduino is not able to communicate with Serial monitor. So the problem is I am able to upload the program by I am not able to read anything serially. Thinks that I have tried/checked

  1. The IDE has the right board selected it is 3.3V Arduino Pro mini with Atmega 328p working at 8MHz. It is set properly

  2. I tried a program which will read the value of a pot and write it to a PWM pin to control the brightness of the LED and the program worked just fine.

  3. Powered the board though Raw and checked my Vcc to be 3.3V so I am using the right board

  4. Used my +5V pro mini with the same programmer and it works just fine

  5. I have selected the 3.3V option on my FTDI board to program my 3.3V pro mini

  6. I tired with different baudrates and nothing worked

2

Found the problem, mine was a Chinese clone so the manufacturer has placed a wrong crystal on my board. Instead of placing a 8MHz he should have placed a 16Mhz or the compiler should have compiled wrong.

I have set the baudrate to 9600 but the serial monitor is able to read data only at 19200 which is twice as that.

Now the question is "Is it safe to use this board? I am not sure what all other problems that I might face with this one because of its wrong crystal value.

3

This is not a "wrong crystal" problem - You chose the wrong processor option (5v 16mhz most likely) when you uploaded to your board.

Got to Tools => Processor => Atmega328p (3.3v 8mhz)

It will all work properly then.

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