Class similar to AnalogIn that uses burst mode to run continious background conversions so when the input is read, the last value can immediatly be returned. This slightly modified version allows NC pins.
Dependents: Pinscape_Controller
Fork of FastAnalogIn by
FastAnalogIn_KLXX_K20D50M.cpp
- Committer:
- mjr
- Date:
- 2015-12-19
- Revision:
- 11:234c5cd2b8de
- Parent:
- 9:31184aa1449c
File content as of revision 11:234c5cd2b8de:
#if defined(TARGET_KLXX) || defined(TARGET_K20D50M) #include "FastAnalogIn.h" #include "clk_freqs.h" #define MAX_FADC 6000000 #define CHANNELS_A_SHIFT 5 #ifdef TARGET_K20D50M static const PinMap PinMap_ADC[] = { {PTC2, ADC0_SE4b, 0}, {PTD1, ADC0_SE5b, 0}, {PTD5, ADC0_SE6b, 0}, {PTD6, ADC0_SE7b, 0}, {PTB0, ADC0_SE8, 0}, {PTB1, ADC0_SE9, 0}, {PTB2, ADC0_SE12, 0}, {PTB3, ADC0_SE13, 0}, {PTC0, ADC0_SE14, 0}, {PTC1, ADC0_SE15, 0}, {NC, NC, 0} }; #endif FastAnalogIn::FastAnalogIn(PinName pin, bool enabled) { if (pin == NC) return; ADCnumber = (ADCName)pinmap_peripheral(pin, PinMap_ADC); if (ADCnumber == (ADCName)NC) { error("ADC pin mapping failed"); } SIM->SCGC6 |= SIM_SCGC6_ADC0_MASK; uint32_t port = (uint32_t)pin >> PORT_SHIFT; SIM->SCGC5 |= 1 << (SIM_SCGC5_PORTA_SHIFT + port); uint32_t cfg2_muxsel = ADC_CFG2_MUXSEL_MASK; if (ADCnumber & (1 << CHANNELS_A_SHIFT)) { cfg2_muxsel = 0; } // bus clk uint32_t PCLK = bus_frequency(); uint32_t clkdiv; for (clkdiv = 0; clkdiv < 4; clkdiv++) { if ((PCLK >> clkdiv) <= MAX_FADC) break; } if (clkdiv == 4) //Set max div clkdiv = 0x7; ADC0->SC1[1] = ADC_SC1_ADCH(ADCnumber & ~(1 << CHANNELS_A_SHIFT)); ADC0->CFG1 = ADC_CFG1_ADIV(clkdiv & 0x3) // Clock Divide Select: (Input Clock)/8 | ADC_CFG1_MODE(3) // (16)bits Resolution | ADC_CFG1_ADICLK(clkdiv >> 2); // Input Clock: (Bus Clock)/2 ADC0->CFG2 = cfg2_muxsel // ADxxb or ADxxa channels | ADC_CFG2_ADACKEN_MASK // Asynchronous Clock Output Enable | ADC_CFG2_ADHSC_MASK; // High-Speed Configuration ADC0->SC2 = ADC_SC2_REFSEL(0); // Default Voltage Reference pinmap_pinout(pin, PinMap_ADC); //Enable channel running = false; enable(enabled); } void FastAnalogIn::enable(bool enabled) { //If currently not running if (!running) { if (enabled) { //Enable the ADC channel ADC0->SC3 |= ADC_SC3_ADCO_MASK; // Enable continuous conversion ADC0->SC1[0] = ADC_SC1_ADCH(ADCnumber & ~(1 << CHANNELS_A_SHIFT)); //Start conversion running = true; } else disable(); } } void FastAnalogIn::disable( void ) { //If currently running if (running) { ADC0->SC3 &= ~ADC_SC3_ADCO_MASK; // Disable continuous conversion } running = false; } uint16_t FastAnalogIn::read_u16() { if (!running) { // start conversion ADC0->SC1[0] = ADC_SC1_ADCH(ADCnumber & ~(1 << CHANNELS_A_SHIFT)); // Wait Conversion Complete while ((ADC0->SC1[0] & ADC_SC1_COCO_MASK) != ADC_SC1_COCO_MASK); } if(running && ((ADC0->SC1[0]&ADC_SC1_ADCH_MASK) != (ADC_SC1_ADCH(ADCnumber & ~(1 << CHANNELS_A_SHIFT))))) { running = false; enable(); while ((ADC0->SC1[0] & ADC_SC1_COCO_MASK) != ADC_SC1_COCO_MASK); } // Return value return (uint16_t)ADC0->R[0]; } #endif //defined TARGET_KLXX