Add a clueboard rev3 (#1688)

* Allow the knight animation to be restricted to a portion of the LED strip

* Add keys for jumping directly to particular animation modes

* Remove orphaned break statements

* Tweak the `RGB_MODE` buttons so they cycle through the same mode.

* small indentation fix

* Add a new revision of the clueboard with 18 underlight LEDs

keyboards/clueboard/rev3/rev3.c

@@ -0,0 +1,63 @@
+#include "rev3.h"
+#include <avr/io.h>
+#include "backlight.h"
+#include "print.h"
+
+void matrix_init_kb(void) {
+	// put your keyboard start-up code here
+	// runs once when the firmware starts up
+	matrix_init_user();
+	led_init_ports();
+
+    // JTAG disable for PORT F. write JTD bit twice within four cycles.
+    MCUCR |= (1<<JTD);
+    MCUCR |= (1<<JTD);
+}
+
+
+void matrix_scan_kb(void) {
+    matrix_scan_user();
+}
+
+void backlight_init_ports(void) {
+    print("init_backlight_pin()\n");
+    // Set our LED pins as output
+    DDRD |= (1<<6); // Esc
+    DDRB |= (1<<7); // Page Up
+    DDRD |= (1<<4); // Arrows
+
+    // Set our LED pins low
+    PORTD &= ~(1<<6); // Esc
+    PORTB &= ~(1<<7); // Page Up
+    PORTD &= ~(1<<4); // Arrows
+}
+
+void backlight_set(uint8_t level) {
+    if ( level == 0 ) {
+        // Turn off light
+        PORTD |= (1<<6); // Esc
+        PORTB |= (1<<7); // Page Up
+        PORTD |= (1<<4); // Arrows
+    } else {
+        // Turn on light
+        PORTD &= ~(1<<6); // Esc
+        PORTB &= ~(1<<7); // Page Up
+        PORTD &= ~(1<<4); // Arrows
+    }
+}
+
+void led_init_ports() {
+    // * Set our LED pins as output
+    DDRB |= (1<<4);
+}
+
+void led_set_kb(uint8_t usb_led) {
+    DDRB |= (1<<4);
+    if (usb_led & (1<<USB_LED_CAPS_LOCK)) {
+        // Turn capslock on
+        PORTB |= (1<<4);
+    } else {
+        // Turn capslock off
+        PORTB &= ~(1<<4);
+    }
+}