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Diffstat (limited to 'quantum/visualizer/example_integration/lcd_backlight_hal.c')
| -rw-r--r-- | quantum/visualizer/example_integration/lcd_backlight_hal.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/quantum/visualizer/example_integration/lcd_backlight_hal.c b/quantum/visualizer/example_integration/lcd_backlight_hal.c new file mode 100644 index 0000000000..913131b169 --- /dev/null +++ b/quantum/visualizer/example_integration/lcd_backlight_hal.c @@ -0,0 +1,91 @@ +/* +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; +} + |