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+# Controller
+## links
+* https://www.kernel.org/doc/Documentation/i2c/dev-interface
+
+## PINs
+* interal = physical = usage
+* 5 = 29 = reset peripheral devices
+* 0 = 27 = I2C SDA
+* 1 = 28 = I2C SCL
+
+## commands
+* reset peripheral devices: `gpioset gpiochip0 5=0`