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I've been having problems with clock drift on one of the projects I've been working on. It's meant to be 3.25 MHz, but it seems to drift down to about 3MHz on occasion. I have been monitoring it on my trusty oscilloscope, but although it can measure frequency if you move the cursors around, it can't keep track of a changing signal. The cursor needs to be moved whenever it changes to check the new reading.
Frequency Counter kit from Sparkfun. This was based on the ATmega328P running at 16MHz, as used on the Arduino. The LCD was a standard HDD44780 based display (as used in my LCD Clocks). The wiring was as follows:
- D2 - RS (LCD)
- D3 - R/W (LCD)
- D4 - E (LCD)
- D5 - Frequency input
- D6 - DB4 (LCD)
- D7 - DB5 (LCD)
- D8 - DB6 (LCD)
- D9 - DB7 (LCD)
- D10 - Backlight Control (LCD)