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-rw-r--r--quantum/visualizer/example_integration/lcd_backlight_hal.c91
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diff --git a/quantum/visualizer/example_integration/lcd_backlight_hal.c b/quantum/visualizer/example_integration/lcd_backlight_hal.c
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+/*
+The MIT License (MIT)
+
+Copyright (c) 2016 Fred Sundvik
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
+
+#include "lcd_backlight.h"
+#include "hal.h"
+
+#define RED_PIN 1
+#define GREEN_PIN 2
+#define BLUE_PIN 3
+#define CHANNEL_RED FTM0->CHANNEL[0]
+#define CHANNEL_GREEN FTM0->CHANNEL[1]
+#define CHANNEL_BLUE FTM0->CHANNEL[2]
+
+#define RGB_PORT PORTC
+#define RGB_PORT_GPIO GPIOC
+
+// Base FTM clock selection (72 MHz system clock)
+// @ 0xFFFF period, 72 MHz / (0xFFFF * 2) = Actual period
+// Higher pre-scalar will use the most power (also look the best)
+// Pre-scalar calculations
+// 0 - 72 MHz -> 549 Hz
+// 1 - 36 MHz -> 275 Hz
+// 2 - 18 MHz -> 137 Hz
+// 3 - 9 MHz -> 69 Hz (Slightly visible flicker)
+// 4 - 4 500 kHz -> 34 Hz (Visible flickering)
+// 5 - 2 250 kHz -> 17 Hz
+// 6 - 1 125 kHz -> 9 Hz
+// 7 - 562 500 Hz -> 4 Hz
+// Using a higher pre-scalar without flicker is possible but FTM0_MOD will need to be reduced
+// Which will reduce the brightness range
+#define PRESCALAR_DEFINE 0
+
+void lcd_backlight_hal_init(void) {
+ // Setup Backlight
+ SIM->SCGC6 |= SIM_SCGC6_FTM0;
+ FTM0->CNT = 0; // Reset counter
+
+ // PWM Period
+ // 16-bit maximum
+ FTM0->MOD = 0xFFFF;
+
+ // Set FTM to PWM output - Edge Aligned, Low-true pulses
+#define CNSC_MODE FTM_SC_CPWMS | FTM_SC_PS(4) | FTM_SC_CLKS(0)
+ CHANNEL_RED.CnSC = CNSC_MODE;
+ CHANNEL_GREEN.CnSC = CNSC_MODE;
+ CHANNEL_BLUE.CnSC = CNSC_MODE;
+
+ // System clock, /w prescalar setting
+ FTM0->SC = FTM_SC_CLKS(1) | FTM_SC_PS(PRESCALAR_DEFINE);
+
+ CHANNEL_RED.CnV = 0;
+ CHANNEL_GREEN.CnV = 0;
+ CHANNEL_BLUE.CnV = 0;
+
+ RGB_PORT_GPIO->PDDR |= (1 << RED_PIN);
+ RGB_PORT_GPIO->PDDR |= (1 << GREEN_PIN);
+ RGB_PORT_GPIO->PDDR |= (1 << BLUE_PIN);
+
+#define RGB_MODE PORTx_PCRn_SRE | PORTx_PCRn_DSE | PORTx_PCRn_MUX(4)
+ RGB_PORT->PCR[RED_PIN] = RGB_MODE;
+ RGB_PORT->PCR[GREEN_PIN] = RGB_MODE;
+ RGB_PORT->PCR[BLUE_PIN] = RGB_MODE;
+}
+
+void lcd_backlight_hal_color(uint16_t r, uint16_t g, uint16_t b) {
+ CHANNEL_RED.CnV = r;
+ CHANNEL_GREEN.CnV = g;
+ CHANNEL_BLUE.CnV = b;
+}
+