High speed analog input class.
Dependents: HighSpeedAnalogIn_TestProgram WallbotR4_BTLE brunoDrome
Diff: HighSpeedAnalogIn.cpp
- Revision:
- 0:db55359719e7
diff -r 000000000000 -r db55359719e7 HighSpeedAnalogIn.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/HighSpeedAnalogIn.cpp Fri Feb 04 22:17:00 2011 +0000 @@ -0,0 +1,292 @@ + +#include "HighSpeedAnalogIn.h" + +HighSpeedAnalogIn *HighSpeedAnalogIn::instance; +int HighSpeedAnalogIn::refcnt = 0; + +HighSpeedAnalogIn::HighSpeedAnalogIn(PinName pin0, PinName pin1, PinName pin2, PinName pin3, PinName pin4, PinName pin5) { + + refcnt++; + if (refcnt > 1) { + error("Please do not use over an object."); + } + + static const int sample_rate = 200000; + static const int cclk_div = 1; + + int adc_clk_freq = CLKS_PER_SAMPLE * sample_rate; + int m = (LPC_SC->PLL0CFG & 0xFFFF) + 1; + int n = (LPC_SC->PLL0CFG >> 16) + 1; + int cclkdiv = LPC_SC->CCLKCFG + 1; + int Fcco = (2 * m * XTAL_FREQ) / n; + int cclk = Fcco / cclkdiv; + + LPC_SC->PCONP |= (1 << 12); + LPC_SC->PCLKSEL0 &= ~(0x3 << 24); + switch (cclk_div) { + case 1: + LPC_SC->PCLKSEL0 |= 0x1 << 24; + break; + case 2: + LPC_SC->PCLKSEL0 |= 0x2 << 24; + break; + case 4: + LPC_SC->PCLKSEL0 |= 0x0 << 24; + break; + case 8: + LPC_SC->PCLKSEL0 |= 0x3 << 24; + break; + default: + fprintf(stderr, "Warning: ADC CCLK clock divider must be 1, 2, 4 or 8. %u supplied.\n", cclk_div); + fprintf(stderr, "Defaulting to 1.\n"); + LPC_SC->PCLKSEL0 |= 0x1 << 24; + break; + } + int pclk = cclk / cclk_div; + int clock_div = pclk / adc_clk_freq; + + if (clock_div > 0xFF) { + fprintf(stderr, "Warning: Clock division is %u which is above 255 limit. Re-Setting at limit.\n", clock_div); + clock_div = 0xFF; + } + if (clock_div == 0) { + fprintf(stderr, "Warning: Clock division is 0. Re-Setting to 1.\n"); + clock_div = 1; + } + + int _adc_clk_freq = pclk / clock_div; + if (_adc_clk_freq > MAX_ADC_CLOCK) { + fprintf(stderr, "Warning: Actual ADC sample rate of %u which is above %u limit\n", _adc_clk_freq / CLKS_PER_SAMPLE, MAX_ADC_CLOCK / CLKS_PER_SAMPLE); + int max_div = 1; + while ((pclk / max_div) > MAX_ADC_CLOCK) { + max_div++; + } + fprintf(stderr, "Maximum recommended sample rate is %u\n", (pclk / max_div) / CLKS_PER_SAMPLE); + } + + LPC_ADC->ADCR = ((clock_div - 1) << 8) | (1 << 21); + LPC_ADC->ADCR &= ~0xFF; + + for (int i = 0; i < 8; i++) { + _adc_data[i] = 0; + } + + // Attach IRQ + instance = this; + NVIC_SetVector(ADC_IRQn, (uint32_t)&static_adcisr); + + // Disable global interrupt + LPC_ADC->ADINTEN &= ~0x100; + + // Clock frequency. + printf("Clock frequency:%d\n", _adc_clk_freq); + + // Actual sampling rate. + printf("Actual sampling rate:%d\n", _adc_clk_freq / CLKS_PER_SAMPLE); + + int tmp = LPC_ADC->ADCR & ~(0x0F << 24); + tmp |= ((0x0 & 7) << 24) | ((0x0 & 1) << 27); + LPC_ADC->ADCR = tmp; + LPC_ADC->ADCR |= (1 << 16); + + if (pin0 != NC) setup(pin0, 1); + if (pin1 != NC) setup(pin1, 1); + if (pin2 != NC) setup(pin2, 1); + if (pin3 != NC) setup(pin3, 1); + if (pin4 != NC) setup(pin4, 1); + if (pin5 != NC) setup(pin5, 1); + + interrupt_state(pin0, 1); +} + +HighSpeedAnalogIn::~HighSpeedAnalogIn() { +} + +void HighSpeedAnalogIn::static_adcisr(void) { + instance->adcisr(); +} + +void HighSpeedAnalogIn::adcisr(void) { + uint32_t stat = LPC_ADC->ADSTAT; + // Scan channels for over-run or done and update array + if (stat & 0x0101) _adc_data[0] = LPC_ADC->ADDR0; + if (stat & 0x0202) _adc_data[1] = LPC_ADC->ADDR1; + if (stat & 0x0404) _adc_data[2] = LPC_ADC->ADDR2; + if (stat & 0x0808) _adc_data[3] = LPC_ADC->ADDR3; + if (stat & 0x1010) _adc_data[4] = LPC_ADC->ADDR4; + if (stat & 0x2020) _adc_data[5] = LPC_ADC->ADDR5; + if (stat & 0x4040) _adc_data[6] = LPC_ADC->ADDR6; + if (stat & 0x8080) _adc_data[7] = LPC_ADC->ADDR7; +} + +int HighSpeedAnalogIn::get_channel(PinName pin) { + int ch; + switch (pin) { + case p15:// =p0.23 of LPC1768 + ch = 0; + break; + case p16:// =p0.24 of LPC1768 + ch = 1; + break; + case p17:// =p0.25 of LPC1768 + ch = 2; + break; + case p18:// =p0.26 of LPC1768 + ch = 3; + break; + case p19:// =p1.30 of LPC1768 + ch = 4; + break; + case p20:// =p1.31 of LPC1768 + ch = 5; + break; + default: + ch = 0; + break; + } + return ch; +} + +uint32_t HighSpeedAnalogIn::get_data(PinName pin) { + // If in burst mode and at least one interrupt enabled then + // take all values from _adc_data + if (LPC_ADC->ADINTEN & 0x3F) { + return (_adc_data[get_channel(pin)]); + } else { + // Return current register value or last value from interrupt + switch (pin) { + case p15:// =p0.23 of LPC1768 + return ((LPC_ADC->ADINTEN & 0x01) ? _adc_data[0] : LPC_ADC->ADDR0); + case p16:// =p0.24 of LPC1768 + return ((LPC_ADC->ADINTEN & 0x02) ? _adc_data[1] : LPC_ADC->ADDR1); + case p17:// =p0.25 of LPC1768 + return ((LPC_ADC->ADINTEN & 0x04) ? _adc_data[2] : LPC_ADC->ADDR2); + case p18:// =p0.26 of LPC1768: + return ((LPC_ADC->ADINTEN & 0x08) ? _adc_data[3] : LPC_ADC->ADDR3); + case p19:// =p1.30 of LPC1768 + return ((LPC_ADC->ADINTEN & 0x10) ? _adc_data[4] : LPC_ADC->ADDR4); + case p20:// =p1.31 of LPC1768 + return ((LPC_ADC->ADINTEN & 0x20) ? _adc_data[5] : LPC_ADC->ADDR5); + default: + return 0; + } + } +} + +// Enable or disable an HighSpeedAnalogIn pin +void HighSpeedAnalogIn::setup(PinName pin, int state) { + int ch = get_channel(pin); + if ((state & 1) == 1) { + switch (pin) { + case p15:// =p0.23 of LPC1768 + LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 14); + LPC_PINCON->PINSEL1 |= (unsigned int)0x1 << 14; + LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 14); + LPC_PINCON->PINMODE1 |= (unsigned int)0x2 << 14; + break; + case p16:// =p0.24 of LPC1768 + LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 16); + LPC_PINCON->PINSEL1 |= (unsigned int)0x1 << 16; + LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 16); + LPC_PINCON->PINMODE1 |= (unsigned int)0x2 << 16; + break; + case p17:// =p0.25 of LPC1768 + LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 18); + LPC_PINCON->PINSEL1 |= (unsigned int)0x1 << 18; + LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 18); + LPC_PINCON->PINMODE1 |= (unsigned int)0x2 << 18; + break; + case p18:// =p0.26 of LPC1768: + LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 20); + LPC_PINCON->PINSEL1 |= (unsigned int)0x1 << 20; + LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 20); + LPC_PINCON->PINMODE1 |= (unsigned int)0x2 << 20; + break; + case p19:// =p1.30 of LPC1768 + LPC_PINCON->PINSEL3 &= ~((unsigned int)0x3 << 28); + LPC_PINCON->PINSEL3 |= (unsigned int)0x3 << 28; + LPC_PINCON->PINMODE3 &= ~((unsigned int)0x3 << 28); + LPC_PINCON->PINMODE3 |= (unsigned int)0x2 << 28; + break; + case p20:// =p1.31 of LPC1768 + LPC_PINCON->PINSEL3 &= ~((unsigned int)0x3 << 30); + LPC_PINCON->PINSEL3 |= (unsigned int)0x3 << 30; + LPC_PINCON->PINMODE3 &= ~((unsigned int)0x3 << 30); + LPC_PINCON->PINMODE3 |= (unsigned int)0x2 << 30; + break; + default: + error("Invalid pin."); + break; + } + // Select channel + LPC_ADC->ADCR |= (1 << ch); + } else { + switch (pin) { + case p15://=p0.23 of LPC1768 + LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 14); + LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 14); + break; + case p16://=p0.24 of LPC1768 + LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 16); + LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 16); + break; + case p17://=p0.25 of LPC1768 + LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 18); + LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 18); + break; + case p18://=p0.26 of LPC1768: + LPC_PINCON->PINSEL1 &= ~((unsigned int)0x3 << 20); + LPC_PINCON->PINMODE1 &= ~((unsigned int)0x3 << 20); + break; + case p19://=p1.30 of LPC1768 + LPC_PINCON->PINSEL3 &= ~((unsigned int)0x3 << 28); + LPC_PINCON->PINMODE3 &= ~((unsigned int)0x3 << 28); + break; + case p20://=p1.31 of LPC1768 + LPC_PINCON->PINSEL3 &= ~((unsigned int)0x3 << 30); + LPC_PINCON->PINMODE3 &= ~((unsigned int)0x3 << 30); + break; + default: + error("Invalid pin."); + break; + } + LPC_ADC->ADCR &= ~(1 << ch); + } +} + +void HighSpeedAnalogIn::interrupt_state(PinName pin, int state) { + int ch = get_channel(pin); + if (state == 1) { + LPC_ADC->ADINTEN &= ~0x100; + LPC_ADC->ADINTEN |= 1 << ch; + /* Enable the HighSpeedAnalogIn Interrupt */ + NVIC_EnableIRQ(ADC_IRQn); + } else { + LPC_ADC->ADINTEN &= ~(1 << ch); + //Disable interrrupt if no active pins left + if ((LPC_ADC->ADINTEN & 0xFF) == 0) + NVIC_DisableIRQ(ADC_IRQn); + } +} + +float HighSpeedAnalogIn::read(PinName pin) { + /* + * Reset DONE and OVERRUN. + * + * bit 31 : DONE + * bit 30 : OVERRUN + */ + _adc_data[get_channel(pin)] &= ~(((uint32_t)0x01 << 31) | ((uint32_t)0x01 << 30)); + return (float)((get_data(pin) >> 4) & 0xFFF) / (float)0xFFF; +} + +unsigned short HighSpeedAnalogIn::read_u16(PinName pin) { + /* + * Reset DONE and OVERRUN. + * + * bit 31 : DONE + * bit 30 : OVERRUN + */ + _adc_data[get_channel(pin)] &= ~(((uint32_t)0x01 << 31) | ((uint32_t)0x01 << 30)); + return ((get_data(pin) >> 4) & 0xFFF); +}