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Diffstat (limited to 'libopencm3/lib/stm32/f1/adc.c')
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1 files changed, 452 insertions, 0 deletions
diff --git a/libopencm3/lib/stm32/f1/adc.c b/libopencm3/lib/stm32/f1/adc.c new file mode 100644 index 0000000..e8be6f9 --- /dev/null +++ b/libopencm3/lib/stm32/f1/adc.c @@ -0,0 +1,452 @@ +/** @defgroup adc_file ADC + +@ingroup STM32F1xx + +@brief <b>libopencm3 STM32F1xx Analog to Digital Converters</b> + +@version 1.0.0 + +@author @htmlonly © @endhtmlonly 2009 +Edward Cheeseman <evbuilder@users.sourceforge.net> +@author @htmlonly © @endhtmlonly 2012 +Ken Sarkies <ksarkies@internode.on.net> + +@date 18 August 2012 + +This library supports the A/D Converter Control System in the STM32F1xx 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. + +Each A/D converter has up to 18 channels: +@li On ADC1 the analog channels 16 and 17 are internally connected to the +temperature +sensor and V<sub>REFINT</sub>, respectively. +@li On ADC2 the analog channels 16 and 17 are internally connected to +V<sub>SS</sub>. +@li On ADC3 the analog channels 9, 14, 15, 16 and 17 are internally connected +to V<sub>SS</sub>. + +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_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 dual mode to independent +(default). Enable triggering for a software trigger. + +@code + rcc_peripheral_enable_clock(&RCC_APB2ENR, RCC_APB2ENR_ADC1EN); + adc_off(ADC1); + rcc_peripheral_reset(&RCC_APB2RSTR, RCC_APB2RSTR_ADC1RST); + rcc_peripheral_clear_reset(&RCC_APB2RSTR, RCC_APB2RSTR_ADC1RST); + rcc_set_adcpre(RCC_CFGR_ADCPRE_PCLK2_DIV2); + adc_set_dual_mode(ADC_CR1_DUALMOD_IND); + adc_disable_scan_mode(ADC1); + adc_set_single_conversion_mode(ADC1); + adc_set_sample_time(ADC1, ADC_CHANNEL0, ADC_SMPR1_SMP_1DOT5CYC); + adc_set_single_channel(ADC1, ADC_CHANNEL0); + adc_enable_trigger(ADC1, ADC_CR2_EXTSEL_SWSTART); + adc_power_on(ADC1); + adc_reset_calibration(ADC1); + adc_calibration(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) 2009 Edward Cheeseman <evbuilder@users.sourceforge.net> + * + * 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 <http://www.gnu.org/licenses/>. + */ + +/* + * Basic ADC handling API. + * + * Examples: + * rcc_peripheral_enable_clock(&RCC_APB2ENR, ADC1EN); + * rcc_peripheral_disable_clock(&RCC_APB2ENR, ADC1EN); + * rcc_peripheral_reset(&RCC_APB2RSTR, ADC1RST); + * rcc_peripheral_clear_reset(&RCC_APB2RSTR, ADC1RST); + * + * rcc_set_adc_clk(ADC_PRE_PLCK2_DIV2); + * adc_set_dual_mode(ADC1, TODO); + * reg16 = adc_read(ADC1, ADC_CH_0); + */ + +/**@{*/ + +#include <libopencm3/stm32/adc.h> + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Power On + +If the ADC is in power-down mode then it is powered up. The application needs +to wait a time of about 3 microseconds for stabilization before using the ADC. +If the ADC is already on this function call has no effect. + * NOTE Common with F37x + +@param[in] adc Unsigned int32. ADC block register address base @ref adc_reg_base +*/ + +void adc_power_on(uint32_t adc) +{ + if (!(ADC_CR2(adc) & ADC_CR2_ADON)) { + ADC_CR2(adc) |= ADC_CR2_ADON; + } +} + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Start a Conversion Without Trigger + +This initiates a conversion by software without a trigger. The ADC needs to be +powered on before this is called, otherwise this function has no effect. + +Note that this is not available in other STM32F families. To ensure code +compatibility, enable triggering and use a software trigger source @see +adc_start_conversion_regular. + +@param[in] adc Unsigned int32. ADC block register address base @ref adc_reg_base +*/ + +void adc_start_conversion_direct(uint32_t adc) +{ + if (ADC_CR2(adc) & ADC_CR2_ADON) { + ADC_CR2(adc) |= ADC_CR2_ADON; + } +} + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Set Dual A/D Mode + +The dual mode uses ADC1 as master and ADC2 in a slave arrangement. This setting +is applied to ADC1 only. Start of conversion when triggered can cause +simultaneous conversion with ADC2, or alternate conversion. Regular and +injected conversions can be configured, each one being separately simultaneous +or alternate. + +Fast interleaved mode starts ADC1 immediately on trigger, and ADC2 seven clock +cycles later. + +Slow interleaved mode starts ADC1 immediately on trigger, and ADC2 fourteen +clock cycles later, followed by ADC1 fourteen cycles later again. This can only +be used on a single channel. + +Alternate trigger mode must occur on an injected channel group, and alternates +between the ADCs on each trigger. + +Note that sampling must not overlap between ADCs on the same channel. + +Dual A/D converter modes possible: + +@li IND: Independent mode. +@li CRSISM: Combined regular simultaneous + injected simultaneous mode. +@li CRSATM: Combined regular simultaneous + alternate trigger mode. +@li CISFIM: Combined injected simultaneous + fast interleaved mode. +@li CISSIM: Combined injected simultaneous + slow interleaved mode. +@li ISM: Injected simultaneous mode only. +@li RSM: Regular simultaneous mode only. +@li FIM: Fast interleaved mode only. +@li SIM: Slow interleaved mode only. +@li ATM: Alternate trigger mode only. + +@param[in] mode Unsigned int32. Dual mode selection from @ref adc_cr1_dualmod +*/ + +void adc_set_dual_mode(uint32_t mode) +{ + ADC1_CR1 |= mode; +} + + + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Enable The Temperature Sensor + +This enables both the sensor and the reference voltage measurements on channels +16 and 17. + +@param[in] adc Unsigned int32. ADC block register address base @ref +adc_reg_base. +*/ + +void adc_enable_temperature_sensor(uint32_t adc) +{ + ADC_CR2(adc) |= ADC_CR2_TSVREFE; +} + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Disable The Temperature Sensor + +Disabling this will reduce power consumption from the sensor and the reference +voltage measurements. + +@param[in] adc Unsigned int32. ADC block register address base @ref +adc_reg_base. +*/ + +void adc_disable_temperature_sensor(uint32_t adc) +{ + ADC_CR2(adc) &= ~ADC_CR2_TSVREFE; +} + + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Enable an External Trigger for Regular Channels + +This enables an external trigger for set of defined regular channels. + +For ADC1 and ADC2 +@li Timer 1 CC1 event +@li Timer 1 CC2 event +@li Timer 1 CC3 event +@li Timer 2 CC2 event +@li Timer 3 TRGO event +@li Timer 4 CC4 event +@li EXTI (TIM8_TRGO is also possible on some devices, see datasheet) +@li Software Start + +For ADC3 +@li Timer 3 CC1 event +@li Timer 2 CC3 event +@li Timer 1 CC3 event +@li Timer 8 CC1 event +@li Timer 8 TRGO event +@li Timer 5 CC1 event +@li Timer 5 CC3 event +@li Software Start + +@param[in] adc Unsigned int32. ADC block register address base @ref +adc_reg_base. +@param[in] trigger Unsigned int8. Trigger identifier @ref adc_trigger_regular_12 +for ADC1 and ADC2, or @ref adc_trigger_regular_3 for ADC3. +*/ + +void adc_enable_external_trigger_regular(uint32_t adc, uint32_t trigger) +{ + uint32_t reg32; + + reg32 = (ADC_CR2(adc) & ~(ADC_CR2_EXTSEL_MASK)); + reg32 |= (trigger); + ADC_CR2(adc) = reg32; + ADC_CR2(adc) |= ADC_CR2_EXTTRIG; +} + +/*---------------------------------------------------------------------------*/ +/** @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_CR2(adc) &= ~ADC_CR2_EXTTRIG; +} + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Enable an External Trigger for Injected Channels + +This enables an external trigger for set of defined injected channels. + +For ADC1 and ADC2 +@li Timer 1 TRGO event +@li Timer 1 CC4 event +@li Timer 2 TRGO event +@li Timer 2 CC1 event +@li Timer 3 CC4 event +@li Timer 4 TRGO event +@li EXTI (TIM8 CC4 is also possible on some devices, see datasheet) +@li Software Start + +For ADC3 +@li Timer 1 TRGO event +@li Timer 1 CC4 event +@li Timer 4 CC3 event +@li Timer 8 CC2 event +@li Timer 8 CC4 event +@li Timer 5 TRGO event +@li Timer 5 CC4 event +@li Software Start + +@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_12 for ADC1 and ADC2, or @ref adc_trigger_injected_3 for +ADC3. +*/ +void adc_enable_external_trigger_injected(uint32_t adc, uint32_t trigger) +{ + uint32_t reg32; + + reg32 = (ADC_CR2(adc) & ~(ADC_CR2_JEXTSEL_MASK)); /* Clear bits [12:14] + */ + reg32 |= (trigger); + ADC_CR2(adc) = reg32; + ADC_CR2(adc) |= ADC_CR2_JEXTTRIG; +} + +/*---------------------------------------------------------------------------*/ +/** @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_CR2(adc) &= ~ADC_CR2_JEXTTRIG; +} + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Initialize Calibration Registers + +This resets the calibration registers. It is not clear if this is required to be +done before every calibration operation. + +@param[in] adc Unsigned int32. ADC block register address base @ref +adc_reg_base. +*/ + +void adc_reset_calibration(uint32_t adc) +{ + ADC_CR2(adc) |= ADC_CR2_RSTCAL; + while (ADC_CR2(adc) & ADC_CR2_RSTCAL); +} + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Calibration + +The calibration data for the ADC is recomputed. The hardware clears the +calibration status flag when calibration is complete. This function does not +return until this happens and the ADC is ready for use. + +The ADC must have been powered down for at least 2 ADC clock cycles, then +powered on. before calibration starts + +@param[in] adc Unsigned int32. ADC block register address base @ref +adc_reg_base. +*/ + +void adc_calibration(uint32_t adc) +{ + ADC_CR2(adc) |= ADC_CR2_CAL; + while (ADC_CR2(adc) & ADC_CR2_CAL); +} + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Power On + +If the ADC is in power-down mode then it is powered up. The application needs +to wait a time of about 3 microseconds for stabilization before using the ADC. +If the ADC is already on this function call will initiate a conversion. + +@deprecated to be removed in a later release + +@param[in] adc Unsigned int32. ADC block register address base @ref +adc_reg_base. +*/ + +void adc_on(uint32_t adc) +{ + ADC_CR2(adc) |= ADC_CR2_ADON; +} + + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Set the Sample Time for a Single Channel + +The sampling time can be selected in ADC clock cycles from 1.5 to 239.5. + +@param[in] adc Unsigned int32. ADC block register address base @ref +adc_reg_base. +@param[in] channel Unsigned int8. ADC Channel integer 0..18 or from @ref +adc_channel. +@param[in] time Unsigned int8. Sampling time selection from @ref adc_sample_rg. + * * NOTE Common with f2 and f37x and f4 +*/ + +void adc_set_sample_time(uint32_t adc, uint8_t channel, uint8_t time) +{ + uint32_t reg32; + + if (channel < 10) { + reg32 = ADC_SMPR2(adc); + reg32 &= ~(0x7 << (channel * 3)); + reg32 |= (time << (channel * 3)); + ADC_SMPR2(adc) = reg32; + } else { + reg32 = ADC_SMPR1(adc); + reg32 &= ~(0x7 << ((channel - 10) * 3)); + reg32 |= (time << ((channel - 10) * 3)); + ADC_SMPR1(adc) = reg32; + } +} + +/*---------------------------------------------------------------------------*/ +/** @brief ADC Set the Sample Time for All Channels + +The sampling time can be selected in ADC clock cycles from 1.5 to 239.5, same +for all channels. + +@param[in] adc Unsigned int32. ADC block register address base @ref +adc_reg_base. +@param[in] time Unsigned int8. Sampling time selection from @ref adc_sample_rg. + * * NOTE Common with f2 and f37x and f4 +*/ + +void adc_set_sample_time_on_all_channels(uint32_t adc, uint8_t time) +{ + uint8_t i; + uint32_t reg32 = 0; + + for (i = 0; i <= 9; i++) { + reg32 |= (time << (i * 3)); + } + ADC_SMPR2(adc) = reg32; + + for (i = 10; i <= 17; i++) { + reg32 |= (time << ((i - 10) * 3)); + } + ADC_SMPR1(adc) = reg32; +} + + +/*---------------------------------------------------------------------------*/ + +/**@}*/ + |