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| #ifndef _CH32V003_TOUCH_H | ||
| #define _CH32V003_TOUCH_H | ||
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| /** ADC-based Capactive Touch Control. | ||
| see cap_touch_adc.c for an example. | ||
| // Enable GPIOD, C and ADC | ||
| RCC->APB2PCENR |= RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOD | RCC_APB2Periph_GPIOC | RCC_APB2Periph_ADC1; | ||
| InitTouchADC(); | ||
| // Then do this any time you want to read some touches. | ||
| sum[0] += ReadTouchPin( GPIOA, 2, 0, iterations ); | ||
| sum[1] += ReadTouchPin( GPIOA, 1, 1, iterations ); | ||
| sum[2] += ReadTouchPin( GPIOC, 4, 2, iterations ); | ||
| sum[3] += ReadTouchPin( GPIOD, 2, 3, iterations ); | ||
| sum[4] += ReadTouchPin( GPIOD, 3, 4, iterations ); | ||
| sum[5] += ReadTouchPin( GPIOD, 5, 5, iterations ); | ||
| sum[6] += ReadTouchPin( GPIOD, 6, 6, iterations ); | ||
| sum[7] += ReadTouchPin( GPIOD, 4, 7, iterations ); | ||
| */ | ||
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| #define TOUCH_ADC_SAMPLE_TIME 2 // Tricky: Don't change this without a lot of experimentation. | ||
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| // Can either be 0 or 1. | ||
| // If 0: Measurement low and rises high. So more pressed is smaller number. | ||
| // If 1: Higher number = harder press. Good to pair with TOUCH_FLAT. | ||
| // If you are doing more prox, use mode 0, otherwise, use mode 1. | ||
| #define TOUCH_SLOPE 1 | ||
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| // If you set this to 1, it will glitch the line, so it will only read | ||
| // anything reasonable if the capacitance can overcome that initial spike. | ||
| // Typically, it seems if you use this you probbly don't need to do | ||
| // any pre-use calibration. | ||
| #define TOUCH_FLAT 0 | ||
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| static void InitTouchADC( ); | ||
| void InitTouchADC( ) | ||
| { | ||
| // ADCCLK = 24 MHz => RCC_ADCPRE = 0: divide sys clock by 2 | ||
| RCC->CFGR0 &= ~(0x1F<<11); | ||
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| // Set up single conversion on chl 2 | ||
| ADC1->RSQR1 = 0; | ||
| ADC1->RSQR2 = 0; | ||
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| // turn on ADC and set rule group to sw trig | ||
| ADC1->CTLR2 |= ADC_ADON | ADC_EXTSEL; | ||
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| // Reset calibration | ||
| ADC1->CTLR2 |= ADC_RSTCAL; | ||
| while(ADC1->CTLR2 & ADC_RSTCAL); | ||
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| // Calibrate | ||
| ADC1->CTLR2 |= ADC_CAL; | ||
| while(ADC1->CTLR2 & ADC_CAL); | ||
| } | ||
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| // Run from RAM to get even more stable timing. | ||
| // This function call takes about 8.1uS to execute. | ||
| static uint32_t ReadTouchPin( GPIO_TypeDef * io, int portpin, int adcno, int iterations ) __attribute__((noinline, section(".srodata"))); | ||
| uint32_t ReadTouchPin( GPIO_TypeDef * io, int portpin, int adcno, int iterations ) | ||
| { | ||
| uint32_t ret = 0; | ||
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| ADC1->RSQR3 = adcno; | ||
| ADC1->SAMPTR2 = TOUCH_ADC_SAMPLE_TIME<<(3*adcno); | ||
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| uint32_t CFGBASE = io->CFGLR & (~(0xf<<(4*portpin))); | ||
| uint32_t CFGFLOAT = ((GPIO_CFGLR_IN_PUPD)<<(4*portpin)) | CFGBASE; | ||
| uint32_t CFGDRIVE = (GPIO_CFGLR_OUT_2Mhz_PP)<<(4*portpin) | CFGBASE; | ||
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| // If we run multiple times with slightly different wait times, we can | ||
| // reduce the impact of the ADC's DNL. | ||
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| #if TOUCH_FLAT == 1 | ||
| #define RELEASEIO io->OUTDR = 1<<(portpin+16*TOUCH_SLOPE); io->CFGLR = CFGFLOAT; | ||
| #else | ||
| #define RELEASEIO io->CFGLR = CFGFLOAT; io->OUTDR = 1<<(portpin+16*TOUCH_SLOPE); | ||
| #endif | ||
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| #define INNER_LOOP( n ) \ | ||
| { \ | ||
| /* Only lock IRQ for a very narrow window. */ \ | ||
| __disable_irq(); \ | ||
| \ | ||
| /* Tricky - we start the ADC BEFORE we transition the pin. By doing \ | ||
| this We are catching it onthe slope much more effectively. */ \ | ||
| ADC1->CTLR2 = ADC_SWSTART | ADC_ADON | ADC_EXTSEL; \ | ||
| \ | ||
| ADD_N_NOPS( n ) \ | ||
| \ | ||
| RELEASEIO \ | ||
| \ | ||
| /* Sampling actually starts here, somewhere, so we can let other \ | ||
| interrupts run */ \ | ||
| __enable_irq(); \ | ||
| while(!(ADC1->STATR & ADC_EOC)); \ | ||
| io->CFGLR = CFGDRIVE; \ | ||
| io->OUTDR = 1<<(portpin+(16*(1-TOUCH_SLOPE))); \ | ||
| ret += ADC1->RDATAR; \ | ||
| } | ||
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| int i; | ||
| for( i = 0; i < iterations; i++ ) | ||
| { | ||
| // Wait a variable amount of time based on loop iteration, in order | ||
| // to get a variety of RC points and minimize DNL. | ||
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| INNER_LOOP( 0 ); | ||
| INNER_LOOP( 2 ); | ||
| INNER_LOOP( 4 ); | ||
| } | ||
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| return ret; | ||
| } | ||
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| #endif | ||
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| /* | ||
| * MIT License | ||
| * | ||
| * Copyright (c) 2023 Valve Corporation | ||
| * | ||
| * 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. | ||
| */ | ||
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