Hi,
I am interested to build this kit but i do not know what oscillator does it have .
Please tell me what oscillator does it have (frequency and type)
Looking at the Dutchtronix site, it is a 20MHz resonator
/mike
Yes, I see it but I do not find to buy this type of resonator .It is ceramic resonator and I found only 16Mhz . I could use one at 16Mhz ?
Just about any crystal or resonator will work. Use appropriate capacitors for whatever you choose.
You will probably have to adjust some constants in the code, if the clock frequency is different than 20 MHz.
Digikey has them (and many resonators above 16 MHz). Try 490-17955-1-ND or similar. (Double check the footprint as I didn’t…)
/mike
Thank you for help. Unfortunately the shipping is expensive (50eur) I will try to put a quartz resonator with smd capacitors
Hi again,
I built this clock I writes the firmware 4.2 I tested on oscilloscope but triggerul on the oscilloscope is 10ms and frequency on the crystal is approximately 40hz .
I tried different firmware but the same result
What is the problem ?
hi,
I tried different crystals but the same result I see the clock on the oscilloscope but the trigger is 10ms and the crystal oscillator(20Mhz) does not work The led green flashes slowly not every seconds . I read the comments from http://www.dutchtronix.com/Sparkfun/Sco … rogramming but i do not find the answer for my issue
Sounds like you did not set the fuses correctly. You have not provided enough information to make any other guesses.
Fuse bits were selected automate when I loaded the firmware .
https://i.postimg.cc/vZ5bYcTP/Untitled- … imizer.jpg
Those fuse setting are INTRC 8MHz internal clock and divide by 8, so the CPU clock is 1 MHz.
For a full swing crystal > 8MHz, uncheck CKDIV8 and set CKSEL 3…0 to 0111 (check CKSEL 3, uncheck CKSEL 2…0).
See the ATmega328p data sheet for an explanation.
If you are not willing to read the ATmega328 data sheet for an explanation on what the fuses mean, and how to set them, perhaps this fuse calculator will be useful.
Thank you .
I set the fusebits as above and now work fine. I used external crystal with capacitors . I hope as will work fine and with cermaic resonator when I have it