嵌入式系統(tǒng)應(yīng)用--adc--模擬電壓采集-肖迎春(編輯修改稿)
2025-06-17 07:26 本頁(yè)面
【文章內(nèi)容簡(jiǎn)介】 Analog watchdog event End of injected conversion End of conversion ADC interrupt to NVIC 21 ADC Regular channels group ? Programmable number of regular channels: Up to 16 channels ? Programmable sample time and order of each channel in the conversion sequence ? Conversion started by: ? Software through start bit ? External trigger generated by: ? Timer1 CC1 ? Timer1 CC2 ? Timer1 CC3 ? Timer2 CC2 ? Timer3 TRGO ? Timer4 CC4 ? EXTI Line11 22 ADC Injected channels group ? Programmable number of injected channels: Up to 4 channels ? Programmable sample time and order of each channel in the conversion sequence ? Conversion started by: ? JAUTO: automatic injected conversion after regular channels conversion ? Software through start bit ? External trigger generated by: ? Timer1 TRGO ? Timer1 CC4 ? Timer2 TRGO ? Timer2 CC1 ? Timer3 CC4 ? Timer4 TRGO ? EXTI Line15 23 Analog sample time ? ADCCLK, up to 14MHz, taken from PCLK2 through a prescaler (Div2, Div4, Div6 and Div8) ? Three bits programmable sample time cycles for each channel: ? cycles ? cycles ? cycles ? cycles ? cycles ? cycles ? cycles ? cycles ? Total conversion = Sample time + cycles (fixed time) @ 14MHz and Sample time= ? total conversion: 1181。s (14 cycles) ADC ADCCLK ADC Prescalers: Div2, Div4, Div6 and Div8 PCLK2 cycles cycles cycles cycles cycles cycles cycles cycles Sample Time Selection SMPx[2:0] 24 ADC conversion modes ? Four conversion mode are available: CHx Start Stop CHx Start Stop . . . CHn CHx Start CHx Start . . . CHn Single channel single conversion mode Multichannels (Scan) single conversion mode Multichannels (Scan) continuous conversion mode Single channel continuous conversion mode 25 ADC discontinuous conversion mode ? Split channels conversion sequence into subsequences ? Available for both regular and injected groups: ? Up to 8 conversion for regular channel ? 1 conversion for injected channel Example: Conversion of channels: 0, 1, 2, 4, 5, 8, 9, 11, 12, 13, 14 and 15 Discontinuous mode Number of channel is 3 Channel0 Channel1 Channel2 Channel4 Channel5 Channel8 Channel9 Channel11 Channel12 Channel13 Channel14 Channel15 1st trigger 2nd trigger 3rd trigger 4th trigger End of Conversion Channel0 Channel1 Channel2 5th trigger … Note: Do not use discontinuous mode for both regular and injected together. It can be used only for one group channel 26 ADC Data alignment ? One bit data align selection: right or left ? For injected channel conversion negative value after subtraction of the offset the sign is extended in right alignment SEXT SEXT SEXT SEXT D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Right alignment 0 0 0 0 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 SEXT 0 0 0 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Left alignment 0 0 0 0 D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 Regular group Injected group Regular group Injected group 27 ADC Analog Watchdogs ? 12bit programmable analog watchdog low and high thresholds ? Enabled on one, some or all converted channels: one regular or/and injected channel, all injected or/and regular channels. ? Interrupt generation on low or high thresholds detection Status Register Analog Watchdog Low Threshold Temp Sensor VREFINT ADC_IN0 ADC_IN1 ADC_IN15 . . . AWD High Threshold 28 DMA ? DMA available only on ADC1 ? DMA request generated on each ADC1 end of regular channel conversion (Not in injected channels) Example: Conversion of regular channels: 0, 1, 2, 3, 4, 5, 6, 7 and 8 Converted ata stored in ConvertedValue_Tab[9] DMA transfer enabled (destination address auto incremented) Channel0 Channel1 Channel2 Channel3 Channel4 Channel5 Channel6 Channel7 Channel8 DMA Request Channel0 conversion result Channel1 conversion resu
醫(yī)療健康相關(guān)推薦
鄂ICP備17016276號(hào)-1