Is it Possible to output the system clock frequency (16MHz) on an Arduino Nano

Using Arduino Project Guidance
1

Hi All,

I am looking to include a CAN-BUS interface in my project, the Can-BUS chip requires a system clock input, which can either be proved by a crystal or an external signal (MCP2515 data sheet)

I have seen other posts it which changes to the bootloader can be made to allow the arduino system clock signal to be output over one of the analog pins, is this equally possible for the nano ??

Also as I am relatively new to this whole process, pointing me in the direction of some relevant tutorials would be much appreciated, as documentation for this sort of thing seem rather sparse...

Many Thanks,

Fintan

2

The PB0 pin (D8?) can become CLKO, by programming the CKOUT fuse.
The rest is up to you, dunno more about programming fuses.

3

Yes, set the CKOUT fuse in boards.txt and then reburn the bootloader with a programmer.
It's bit 6 in the low fuse byte.

Change this:
nano328.bootloader.low_fuses=0xFF
to
nano328.bootloader.low_fuses=0xBF

4

CrossRoads:
Yes, set the CKOUT fuse in boards.txt and then reburn the bootloader with a programmer.
It's bit 6 in the low fuse byte.

Change this:
nano328.bootloader.low_fuses=0xFF
to
nano328.bootloader.low_fuses=0xBF

Or use avrdude from the command line to set the fuse

Or use a USBAsp and eXtremeBurner (or other comparable utility) to change the fuse.

5

CrossRoads:
Yes, set the CKOUT fuse in boards.txt and then reburn the bootloader with a programmer.
It's bit 6 in the low fuse byte.

Change this:
nano328.bootloader.low_fuses=0xFF
to
nano328.bootloader.low_fuses=0xBF

Thank you for the Help, I have done the steps quoted and burned the bootloader via an uno I had lying around. How did you find these fuse settings out though? and do you agree with Br Diettrich that this will be output on pin D8? ( I don't have an oscilloscope handy else I could easily check myself ...)

Many Thanks,

Fintan

6

What about the datasheet of the ATmega328?

Or just plain old Google?