24Mhz High Precision Crystal Clock Oscillator

Other Hardware 3rd Party Boards
1

I was browsing around on eBay and came upon these 24Mhz Clock Crystals and was wondering if it was possible to upgrade the close of my Pro Mini Ardunio. Have anyone tried this?

Thank you.

http://cgi.ebay.com/5-x-24Mhz-High-Precision-Crystal-Clock-Oscillator_W0QQitemZ300530157957QQcategoryZ16145QQcmdZViewItemQQ_trksidZp5197.m263QQ_trkparmsZalgo%3DSIC%26itu%3DUCI%252BIA%252BUA%252BFICS%252BUFI%252BDDSIC%26otn%3D10%26pmod%3D380327208085%252B280602239060%252B310180759687%26po%3DLVI%26ps%3D63%26clkid%3D8414260650658597966

2

24 MHz is beyond the specifications. Others have reported success over-clocking AVR processors but it is always a gamble. It is your application so you will have to decide if it is worth the risk.

3

See section 8.2 of the ATMega328 datasheet for more discussion of the crystals to use.

See this note in particular from Tables 8-3 & 8-5.
"If the crystal frequency exceeds the specification of the device (depends on VCC), the CKDIV8
Fuse can be programmed in order to divide the internal frequency by 8. It must be ensured
that the resulting divided clock meets the frequency specification of the device."

4

Thanks for the post. I assumed CKDIV8 only applied to the internal oscillator.

5

Nothing like making life difficult. Other than the technical implications of whether it will run at 24Mhz, it will introduce a lot of non-trivial timing issues, particularly with serial and uploading sketches.