A Pro-mini 328 running half speed????

Relativly new to this…

I have bought two Arduino Pro Mini 328 - 5V/16MHz, and worked great for the first couple of times i uploaded the programs, thru the ftdi port.

my program has the green led blink every second or so (to indicate a cycle of my program), and I have the same program in both units.

With one of the mini pros, I am able to program it thru the ftdi port (serial), while the other will not… anymore.

I can program both units with my my stk500 in (bascom, as well thru AVR studio), but the code that i am running is not running at the correct speed.

The mini pro that I can not read from the ftdi port, blinks once every 10s or so… really slow, while the other blinks at about 2s. could it be an issue with the resonator?

I have the same code ported to an atmega32 running at 16mhz, and it works great… blinks every second. give or take a few ms.

I have tried to reload the bootloader in the the one unit , and it programs ok, but it will still blink slower then the atmegs32. i’m assuming there is a difference between the 8mhz and 16mhz bootloader? and haved used the different hex supplied by the Arduino 017 software.

I program the bootloader with my stk500 thru AVR Studio. It only gives me a max clock of 8mhz in the fuse settings. could this be causing my issues? is there way to change that?

can i use another program to program this?

am i completely missing something?

Sounds like you may have the ckdiv8 fuse set (and may also be running on the internal 8MHz oscillator). ckdiv8 divides the clock by a factor of 8. If you are running at the wrong frequency, the serial port won’t work either since the main oscillator is used to generate the baud rate clock.

/mike