Calibrating the ClockGen - sanni/cartreader GitHub Wiki

To calibrate the Clock Generator you first need to enable it in config.h by removing // in front of the following two options:

/****/

/* [ SNES Core/CLOCKGEN: Read Clock Generator Calibration Data ---- ]
    Toggle clock calibration menu and whether or not to use calibration data from snes_clk.txt
*/

#define OPTION_CLOCKGEN_CALIBRATION
#define OPTION_CLOCKGEN_USE_CALIBRATION

Then you find a new menu entry under "Super Nintendo/SFC" called "Calibrate Clock". Once the calibration function was loaded place one end of a jumper wire against SNES slot pin 43(A18/BA2) and the other end of the wire against one of the following pins and it should read those values:

  • 3072000.00 Hz when connected to SNES slot pin 56(CIC Clock)
  • 4000000.00 Hz when connected to SNES slot pin 1(EXT Clock)
  • 1000000.00 Hz when connected to SNES slot pin 57(CPU Clock)

IMG_3882

Once you have adjusted the clock to match the values more closely hold the button for a very long time and let it go to save the setting.

Video:
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