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Replace PWM RSSI with ADC RSSI.

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The primary reason is to support the D4R-II with it's much faster PWM
frequency.  The PWM RSSI code could not keep up, and since there are no
timers free for using capture compare of PWM signals in hardware one
solution is to use the ADC at a slow sample rate.

RC2 is used as before and it expects a signal between 0 and 3.3v.  An
inline smoothing capacitor may help.

This commit also removes the cli command adc_power_channel since the
reading was never actually exposed anywhere.
This commit is contained in:
Dominic Clifton 2014-05-28 03:19:10 +01:00
parent 4c9f9093b8
commit 5484e5fddd
15 changed files with 97 additions and 128 deletions
Download patch file Download diff file Expand all files Collapse all files

20
src/drivers/adc_stm32f10x.c
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@ -14,8 +14,9 @@
// Driver for STM32F103CB onboard ADC
// VBAT is connected to PA4 (ADC1_IN4) with 10k:1k divider
// rev.5 hardware has PA5 (ADC1_IN5) on breakout pad on bottom of board
// Additional channel can be stolen from RC_CH2 (PA1, ADC1_IN1) or
// RC_CH8 (PB1, ADC1_IN9) by using set power_adc_channel=1|9
//
// RSSI ADC uses PA1
// An additional ADC source is available on CH8 (PB1, ADC1_IN9)
extern adc_config_t adcConfig[ADC_CHANNEL_COUNT];
extern volatile uint16_t adcValues[ADC_CHANNEL_COUNT];
@ -33,18 +34,21 @@ void adcInit(drv_adc_config_t *init)
adcConfig[ADC_BATTERY].adcChannel = ADC_Channel_4;
adcConfig[ADC_BATTERY].dmaIndex = configuredAdcChannels++;
adcConfig[ADC_BATTERY].enabled = true;
adcConfig[ADC_BATTERY].sampleTime = ADC_SampleTime_28Cycles5;
// optional ADC5 input on rev.5 hardware
if (hse_value == 12000000) {
adcConfig[ADC_EXTERNAL1].adcChannel = ADC_Channel_5;
adcConfig[ADC_EXTERNAL1].dmaIndex = configuredAdcChannels++;
adcConfig[ADC_EXTERNAL1].enabled = true;
adcConfig[ADC_EXTERNAL1].sampleTime = ADC_SampleTime_28Cycles5;
}
// another channel can be stolen from PWM for current measurement or other things
if (init->powerAdcChannel > 0) {
adcConfig[ADC_EXTERNAL2].adcChannel = ADC_Channel_1; // init->powerAdcChannel;
adcConfig[ADC_EXTERNAL2].dmaIndex = configuredAdcChannels++;
adcConfig[ADC_EXTERNAL2].enabled = true;
if (init->enableRSSI > 0) {
adcConfig[ADC_RSSI].adcChannel = ADC_Channel_1;
adcConfig[ADC_RSSI].dmaIndex = configuredAdcChannels++;
adcConfig[ADC_RSSI].enabled = true;
adcConfig[ADC_RSSI].sampleTime = ADC_SampleTime_239Cycles5;
}
// ADC driver assumes all the GPIO was already placed in 'AIN' mode
@ -76,7 +80,7 @@ void adcInit(drv_adc_config_t *init)
if (!adcConfig[i].enabled) {
continue;
}
ADC_RegularChannelConfig(ADC1, adcConfig[i].adcChannel, rank++, ADC_SampleTime_28Cycles5);
ADC_RegularChannelConfig(ADC1, adcConfig[i].adcChannel, rank++, adcConfig[i].sampleTime);
}
ADC_DMACmd(ADC1, ENABLE);