/** @defgroup adc_file ADC * * @ingroup STM32F3xx * * @brief libopencm3 STM32F3xx Analog to Digital Converters * * @author @htmlonly © @endhtmlonly 2012 * Ken Sarkies * * @date 30 August 2012 * * This library supports the A/D Converter Control System in the STM32 series * of ARM Cortex Microcontrollers by ST Microelectronics. * * Devices can have up to three A/D converters each with their own set of * registers. However all the A/D converters share a common clock which is * prescaled from the APB2 clock by default by a minimum factor of 2 to a * maximum of 8. The ADC resolution can be set to 12, 10, 8 or 6 bits. * * Each A/D converter has up to 19 channels: * @li On ADC1 the analog channels 16 is internally connected to the * temperature sensor, channel 17 to VREFINT, and channel 18 * to VBATT. * @li On ADC2 and ADC3 the analog channels 16 - 18 are not used. * * The conversions can occur as a one-off conversion whereby the process stops * once conversion is complete. The conversions can also be continuous wherein * a new conversion starts immediately the previous conversion has ended. * * Conversion can occur as a single channel conversion or a scan of a group of * channels in either continuous or one-off mode. If more than one channel is * converted in a scan group, DMA must be used to transfer the data as there is * only one result register available. An interrupt can be set to occur at the * end* * of conversion, which occurs after all channels have been scanned. * * A discontinuous mode allows a subgroup of group of a channels to be * converted in bursts of a given length. * * Injected conversions allow a second group of channels to be converted * separately from the regular group. An interrupt can be set to occur at the * end of conversion, which occurs after all channels have been scanned. * * @section adc_f3_api_ex Basic ADC Handling API. * * Example 1: Simple single channel conversion polled. Enable the peripheral * clock and ADC, reset ADC and set the prescaler divider. Set multiple mode to * independent. * * @code * gpio_mode_setup(GPIOA, GPIO_MODE_ANALOG, GPIO_PUPD_NONE, GPIO1); * rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_ADC1EN); * adc_set_clk_prescale(RCC_CFGR_ADCPRE_BY2); * adc_disable_scan_mode(ADC1); * adc_set_single_conversion_mode(ADC1); * adc_set_sample_time(ADC1, ADC_CHANNEL0, ADC_SMPR1_SMP_1DOT5CYC); * uint8_t channels[] = ADC_CHANNEL0; * adc_set_regular_sequence(ADC1, 1, channels); * adc_set_multi_mode(ADC_CCR_MULTI_INDEPENDENT); * adc_power_on(ADC1); * adc_start_conversion_regular(ADC1); * while (! adc_eoc(ADC1)); * reg16 = adc_read_regular(ADC1); * @endcode * * LGPL License Terms @ref lgpl_license */ /* * This file is part of the libopencm3 project. * * Copyright (C) 2012 Ken Sarkies * * This library is free software: you can redistribute it and/or modify * it under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this library. If not, see . */ #include /**@{*/ /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Analog Watchdog for Regular Conversions * * The analog watchdog allows the monitoring of an analog signal between two * threshold levels. The thresholds must be preset. Comparison is done before * data alignment takes place, so the thresholds are left-aligned. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_analog_watchdog_regular(uint32_t adc) { ADC_CFGR1(adc) |= ADC_CFGR1_AWD1EN; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Analog Watchdog for Regular Conversions * * The analog watchdog allows the monitoring of an analog signal between two * threshold levels. The thresholds must be preset. Comparison is done before * data alignment takes place, so the thresholds are left-aligned. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_analog_watchdog_regular(uint32_t adc) { ADC_CFGR1(adc) &= ~ADC_CFGR1_AWD1EN; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Analog Watchdog for Injected Conversions * * The analog watchdog allows the monitoring of an analog signal between two * threshold levels. The thresholds must be preset. Comparison is done before * data alignment takes place, so the thresholds are left-aligned. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_analog_watchdog_injected(uint32_t adc) { ADC_CFGR1(adc) |= ADC_CFGR1_JAWD1EN; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable Analog Watchdog for Injected Conversions * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_analog_watchdog_injected(uint32_t adc) { ADC_CFGR1(adc) &= ~ADC_CFGR1_JAWD1EN; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Discontinuous Mode for Regular Conversions * * In this mode the ADC converts, on each trigger, a subgroup of up to 8 of the * defined regular channel group. The subgroup is defined by the number of * consecutive channels to be converted. After a subgroup has been converted * the next trigger will start conversion of the immediately following subgroup * of the same length or until the whole group has all been converted. When the * whole group has been converted, the next trigger will restart conversion of * the subgroup at the beginning of the whole group. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base @param[in] length Unsigned int8. Number of channels in the * group @ref adc_cr1_discnum */ void adc_enable_discontinuous_mode_regular(uint32_t adc, uint8_t length) { if ((length-1) > 7) { return; } ADC_CFGR1(adc) |= ADC_CFGR1_DISCEN; ADC_CFGR1(adc) |= ((length-1) << ADC_CFGR1_DISCNUM_SHIFT); } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable Discontinuous Mode for Regular Conversions * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_discontinuous_mode_regular(uint32_t adc) { ADC_CFGR1(adc) &= ~ADC_CFGR1_DISCEN; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Discontinuous Mode for Injected Conversions * * In this mode the ADC converts sequentially one channel of the defined group * of injected channels, cycling back to the first channel in the group once * the entire group has been converted. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_discontinuous_mode_injected(uint32_t adc) { ADC_CFGR1(adc) |= ADC_CFGR1_JDISCEN; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable Discontinuous Mode for Injected Conversions * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_discontinuous_mode_injected(uint32_t adc) { ADC_CFGR1(adc) &= ~ADC_CFGR1_JDISCEN; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Automatic Injected Conversions * * The ADC converts a defined injected group of channels immediately after the * regular channels have been converted. The external trigger on the injected * channels is disabled as required. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_automatic_injected_group_conversion(uint32_t adc) { adc_disable_external_trigger_injected(adc); ADC_CFGR1(adc) |= ADC_CFGR1_JAUTO; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable Automatic Injected Conversions * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_automatic_injected_group_conversion(uint32_t adc) { ADC_CFGR1(adc) &= ~ADC_CFGR1_JAUTO; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Analog Watchdog for All Regular and/or Injected Channels * * The analog watchdog allows the monitoring of an analog signal between two * threshold levels. The thresholds must be preset. Comparison is done before * data alignment takes place, so the thresholds are left-aligned. * * @note The analog watchdog must be enabled for either or both of the regular * or injected channels. If neither are enabled, the analog watchdog feature * will be disabled. * * @ref adc_enable_analog_watchdog_injected, @ref * adc_enable_analog_watchdog_regular. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_analog_watchdog_on_all_channels(uint32_t adc) { ADC_CFGR1(adc) &= ~ADC_CFGR1_AWD1SGL; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Analog Watchdog for a Selected Channel * * The analog watchdog allows the monitoring of an analog signal between two * threshold levels. The thresholds must be preset. Comparison is done before * data alignment takes place, so the thresholds are left-aligned. * * @note The analog watchdog must be enabled for either or both of the regular * or injected channels. If neither are enabled, the analog watchdog feature * will be disabled. If both are enabled, the same channel number is monitored * @ref adc_enable_analog_watchdog_injected, @ref * adc_enable_analog_watchdog_regular. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base * @param[in] channel Unsigned int8. ADC channel numbe * @ref adc_watchdog_channel */ void adc_enable_analog_watchdog_on_selected_channel(uint32_t adc, uint8_t channel) { uint32_t reg32; reg32 = (ADC_CFGR1(adc) & ~ADC_CFGR1_AWD1CH); /* Clear bit [4:0]. */ if (channel < 18) { reg32 |= channel; } ADC_CFGR1(adc) = reg32; ADC_CFGR1(adc) |= ADC_CFGR1_AWD1SGL; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Injected End-Of-Conversion Interrupt * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_eoc_interrupt_injected(uint32_t adc) { ADC_IER(adc) |= ADC_IER_JEOCIE; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable Injected End-Of-Conversion Interrupt * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_eoc_interrupt_injected(uint32_t adc) { ADC_IER(adc) &= ~ADC_IER_JEOCIE; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Injected End-Of-Sequence Interrupt * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_eos_interrupt_injected(uint32_t adc) { ADC_IER(adc) |= ADC_IER_JEOSIE; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable Injected End-Of-Sequence Interrupt * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_eos_interrupt_injected(uint32_t adc) { ADC_IER(adc) &= ~ADC_IER_JEOSIE; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Analog Watchdog Interrupt * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_all_awd_interrupt(uint32_t adc) { ADC_IER(adc) |= ADC_IER_AWD1IE; ADC_IER(adc) |= ADC_IER_AWD2IE; ADC_IER(adc) |= ADC_IER_AWD3IE; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable Analog Watchdog Interrupt * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_all_awd_interrupt(uint32_t adc) { ADC_IER(adc) &= ~ADC_IER_AWD1IE; ADC_IER(adc) &= ~ADC_IER_AWD2IE; ADC_IER(adc) &= ~ADC_IER_AWD3IE; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable Regular End-Of-Sequence Interrupt * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_enable_eos_interrupt(uint32_t adc) { ADC_IER(adc) |= ADC_IER_EOSIE; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable Regular End-Of-Sequence Interrupt * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_eos_interrupt(uint32_t adc) { ADC_IER(adc) &= ~ADC_IER_EOSIE; } /*---------------------------------------------------------------------------*/ /** @brief ADC Software Triggered Conversion on Injected Channels * * This starts conversion on a set of defined injected channels. It is cleared * by hardware once conversion starts. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_start_conversion_injected(uint32_t adc) { /* Start conversion on injected channels. */ ADC_CR(adc) |= ADC_CR_JADSTART; /* Wait until the ADC starts the conversion. */ while (ADC_CR(adc) & ADC_CR_JADSTART); } /*---------------------------------------------------------------------------*/ /** @brief ADC Set Analog Watchdog Upper Threshold * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base * @param[in] threshold Unsigned int8. Upper threshold value */ void adc_set_watchdog_high_threshold(uint32_t adc, uint8_t threshold) { uint32_t reg32 = 0; reg32 |= (threshold << 16); reg32 &= ~0xff00ffff; /* Clear all bits above 8. */ ADC_TR1(adc) = reg32; ADC_TR2(adc) = reg32; ADC_TR3(adc) = reg32; } /*---------------------------------------------------------------------------*/ /** @brief ADC Set Analog Watchdog Lower Threshold * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base * @param[in] threshold Unsigned int8. Lower threshold value */ void adc_set_watchdog_low_threshold(uint32_t adc, uint8_t threshold) { uint32_t reg32 = 0; reg32 = (uint32_t)threshold; reg32 &= ~0xffffff00; /* Clear all bits above 8. */ ADC_TR1(adc) = reg32; ADC_TR2(adc) = reg32; ADC_TR3(adc) = reg32; } /*---------------------------------------------------------------------------*/ /** @brief ADC Set an Injected Channel Conversion Sequence * * Defines a sequence of channels to be converted as an injected group with a * length from 1 to 4 channels. If this is called during conversion, the current * conversion is reset and conversion begins again with the newly defined group. * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base * @param[in] length Unsigned int8. Number of channels in the group. * @param[in] channel Unsigned int8[]. Set of channels in sequence, integers * 0..18 */ void adc_set_injected_sequence(uint32_t adc, uint8_t length, uint8_t channel[]) { uint32_t reg32 = 0; uint8_t i = 0; /* Maximum sequence length is 4 channels. Minimum sequence is 1.*/ if ((length - 1) > 3) { return; } for (i = 0; i < length; i++) { reg32 |= ADC_JSQR_JSQ_VAL(4 - i, channel[length - i - 1]); } reg32 |= ADC_JSQR_JL_VAL(length); ADC_JSQR(adc) = reg32; } /*---------------------------------------------------------------------------*/ /** @brief ADC Read the End-of-Conversion Flag for Injected Conversion * * This flag is set by hardware at the end of each injected conversion of a * channel when a new data is available in the corresponding ADCx_JDRy register. * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base * @returns bool. End of conversion flag. */ bool adc_eoc_injected(uint32_t adc) { return ADC_ISR(adc) & ADC_ISR_JEOC; } /*---------------------------------------------------------------------------*/ /** @brief ADC Read the End-of-Sequence Flag for Injected Conversions * * This flag is set after all channels of an injected group have been * converted. * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base * @returns bool. End of conversion flag. */ bool adc_eos_injected(uint32_t adc) { return ADC_ISR(adc) & ADC_ISR_JEOS; } /*---------------------------------------------------------------------------*/ /** @brief ADC Read from an Injected Conversion Result Register * * The result read back from the selected injected result register (one of four) * is 12 bits, right or left aligned within the first 16 bits. The result can * have a negative value if the injected channel offset has been set @see * adc_set_injected_offset. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base * @param[in] reg Unsigned int8. Register number (1 ... 4). * @returns Unsigned int32 conversion result. */ uint32_t adc_read_injected(uint32_t adc, uint8_t reg) { switch (reg) { case 1: return ADC_JDR1(adc); case 2: return ADC_JDR2(adc); case 3: return ADC_JDR3(adc); case 4: return ADC_JDR4(adc); } return 0; } /*---------------------------------------------------------------------------*/ /** @brief ADC Set the Injected Channel Data Offset * * This value is subtracted from the injected channel results after conversion * is complete, and can result in negative results. A separate value can be * specified for each injected data register. * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base * @param[in] reg Unsigned int8. Register number (1 ... 4). * @param[in] offset Unsigned int32. */ void adc_set_injected_offset(uint32_t adc, uint8_t reg, uint32_t offset) { switch (reg) { case 1: ADC_OFR1(adc) |= ADC_OFR1_OFFSET1_EN; ADC_OFR1(adc) |= offset; break; case 2: ADC_OFR2(adc) |= ADC_OFR2_OFFSET2_EN; ADC_OFR2(adc) |= offset; break; case 3: ADC_OFR3(adc) |= ADC_OFR3_OFFSET3_EN; ADC_OFR3(adc) |= offset; break; case 4: ADC_OFR4(adc) |= ADC_OFR4_OFFSET4_EN; ADC_OFR4(adc) |= offset; break; } } /*---------------------------------------------------------------------------*/ /** @brief ADC Set Clock Prescale * * The ADC clock taken from the APB2 clock can be scaled down by 2, 4, 6 or 8. * * @param[in] prescale Unsigned int32. Prescale value for ADC Clock @ref * adc_ccr_adcpre */ void adc_set_clk_prescale(uint32_t adc, uint32_t prescale) { uint32_t reg32 = ((ADC_CCR(adc) & ~ADC_CCR_CKMODE_MASK) | prescale); ADC_CCR(adc) = reg32; } /*---------------------------------------------------------------------------*/ /** @brief ADC Set Dual/Triple Mode * * The multiple mode uses ADC1 as master, ADC2 and optionally ADC3 in a slave * arrangement. This setting is applied to ADC1 only. * * The various modes possible are described in the reference manual. * * @param[in] mode Unsigned int32. Multiple mode selection from @ref * adc_multi_mode */ void adc_set_multi_mode(uint32_t adc, uint32_t mode) { ADC_CCR(adc) |= mode; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable an External Trigger for Regular Channels * * This enables an external trigger for set of defined regular channels, and * sets the polarity of the trigger event: rising or falling edge or both. Note * that if the trigger polarity is zero, triggering is disabled. * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base * @param[in] trigger Unsigned int32. Trigger identifier * @ref adc_trigger_regular * @param[in] polarity Unsigned int32. Trigger polarity @ref * adc_trigger_polarity_regular */ void adc_enable_external_trigger_regular(uint32_t adc, uint32_t trigger, uint32_t polarity) { uint32_t reg32 = ADC_CFGR1(adc); reg32 &= ~(ADC_CFGR1_EXTSEL_MASK | ADC_CFGR1_EXTEN_MASK); reg32 |= (trigger | polarity); ADC_CFGR1(adc) = reg32; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable an External Trigger for Regular Channels * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base */ void adc_disable_external_trigger_regular(uint32_t adc) { ADC_CFGR1(adc) &= ~ADC_CFGR1_EXTEN_MASK; } /*---------------------------------------------------------------------------*/ /** @brief ADC Enable an External Trigger for Injected Channels * * This enables an external trigger for set of defined injected channels, and * sets the polarity of the trigger event: rising or falling edge or both. * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base * @param[in] trigger Unsigned int8. Trigger identifier * @ref adc_trigger_injected * @param[in] polarity Unsigned int32. Trigger polarity * @ref adc_trigger_polarity_injected */ void adc_enable_external_trigger_injected(uint32_t adc, uint32_t trigger, uint32_t polarity) { uint32_t reg32 = ADC_JSQR(adc); reg32 &= ~(ADC_JSQR_JEXTSEL_MASK | ADC_JSQR_JEXTEN_MASK); reg32 |= (trigger | polarity); ADC_JSQR(adc) = reg32; } /*---------------------------------------------------------------------------*/ /** @brief ADC Disable an External Trigger for Injected Channels * * @param[in] adc Unsigned int32. ADC block register address base @ref * adc_reg_base */ void adc_disable_external_trigger_injected(uint32_t adc) { ADC_JSQR(adc) &= ~ADC_JSQR_JEXTEN_MASK; } /*---------------------------------------------------------------------------*/ /** @brief ADC Read the Analog Watchdog Flag * * This flag is set when the converted voltage crosses the high or low * thresholds. * * @param[in] adc Unsigned int32. ADC block register address base * @ref adc_reg_base * @returns bool. AWD flag. */ bool adc_awd(uint32_t adc) { return (ADC_ISR(adc) & ADC_ISR_AWD1) && (ADC_ISR(adc) & ADC_ISR_AWD2) && (ADC_ISR(adc) & ADC_ISR_AWD3); } /** * Enable the ADC Voltage regulator * Before any use of the ADC, the ADC Voltage regulator must be enabled. * You must wait up to 10uSecs afterwards before trying anything else. * @param[in] adc ADC block register address base * @sa adc_disable_regulator */ void adc_enable_regulator(uint32_t adc) { ADC_CR(adc) &= ~ADC_CR_ADVREGEN_MASK; ADC_CR(adc) |= ADC_CR_ADVREGEN_ENABLE; } /** * Disable the ADC Voltage regulator * You can disable the adc vreg when not in use to save power * @param[in] adc ADC block register address base * @sa adc_enable_regulator */ void adc_disable_regulator(uint32_t adc) { ADC_CR(adc) &= ~ADC_CR_ADVREGEN_MASK; ADC_CR(adc) |= ADC_CR_ADVREGEN_DISABLE; } /**@}*/