Mercurial > public > ostc4
view Small_CPU/Src/externalInterface.c @ 615:556df4a8f418
Moved non critical functions from timer interrupt to main loop:
Especially the drawing of the minilog could potentially cause an overrun of the timer interrupt without need => Moved to main loop.
author | Ideenmodellierer |
---|---|
date | Wed, 27 Jan 2021 21:56:48 +0100 |
parents | 011d8f9f5ddb |
children | 1b995079c045 |
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/** ****************************************************************************** * @file externalInterface.c * @author heinrichs weikamp gmbh * @version V0.0.1 * @date 07-Nov-2020 * @brief Interface functionality to proceed external analog signal via i2c connection * @verbatim ============================================================================== ##### stm32f4xx_hal_i2c.c modification ##### ============================================================================== The LTC2942 requires an repeated start condition without stop condition for data reception. @endverbatim ****************************************************************************** * @attention * * <h2><center>© COPYRIGHT(c) 2014 heinrichs weikamp</center></h2> * ****************************************************************************** */ /* Includes ------------------------------------------------------------------*/ #include <math.h> #include "i2c.h" #include "externalInterface.h" #include "scheduler.h" extern SGlobal global; #define ADC_ANSWER_LENGTH (5u) /* 3424 will provide addr + 4 data bytes */ #define ADC_TIMEOUT (10u) /* conversion stuck for unknown reason => restart */ #define ADC_REF_VOLTAGE_MV (2048.0f) /* reference voltage of MPC3424*/ #define ADC_START_CONVERSION (0x80) #define ADC_GAIN_4 (0x02) #define ADC_GAIN_4_VALUE (4.0f) #define ADC_GAIN_8 (0x03) #define ADC_GAIN_8_VALUE (8.0f) #define ADC_RESOLUTION_16BIT (0x08) #define ADC_RESOLUTION_16BIT_VALUE (16u) #define ADC_RESOLUTION_18BIT (0x0C) #define ADC_RESOLUTION_18BIT_VALUE (18u) #define ANSWER_CONFBYTE_INDEX (4u) static uint8_t activeChannel = 0; /* channel which is in request */ static uint8_t recBuf[ADC_ANSWER_LENGTH]; static uint8_t timeoutCnt = 0; static uint8_t externalInterfacePresent = 0; float externalChannel_mV[MAX_ADC_CHANNEL]; void externalInterface_Init(void) { activeChannel = 0; timeoutCnt = 0; externalInterfacePresent = 0; if(externalInterface_StartConversion(activeChannel) == HAL_OK) { externalInterfacePresent = 1; global.deviceDataSendToMaster.hw_Info.extADC = 1; } global.deviceDataSendToMaster.hw_Info.checkADC = 1; } uint8_t externalInterface_StartConversion(uint8_t channel) { uint8_t retval = 0; uint8_t confByte = 0; if(channel < MAX_ADC_CHANNEL) { confByte = ADC_START_CONVERSION | ADC_RESOLUTION_16BIT | ADC_GAIN_8; confByte |= channel << 5; retval = I2C_Master_Transmit(DEVICE_EXTERNAL_ADC, &confByte, 1); } return retval; } /* Check if conversion is done and trigger measurement of next channel */ uint8_t externalInterface_ReadAndSwitch() { uint8_t retval = EXTERNAL_ADC_NO_DATA; if(externalInterfacePresent) { if(I2C_Master_Receive(DEVICE_EXTERNAL_ADC, recBuf, ADC_ANSWER_LENGTH) == HAL_OK) { if((recBuf[ANSWER_CONFBYTE_INDEX] & ADC_START_CONVERSION) == 0) /* !ready set => received data contains new value */ { retval = activeChannel; /* return channel number providing new data */ activeChannel++; if(activeChannel == MAX_ADC_CHANNEL) { activeChannel = 0; } externalInterface_StartConversion(activeChannel); timeoutCnt = 0; } else { if(timeoutCnt++ >= ADC_TIMEOUT) { externalInterface_StartConversion(activeChannel); timeoutCnt = 0; } } } else /* take also i2c bus disturb into account */ { if(timeoutCnt++ >= ADC_TIMEOUT) { externalInterface_StartConversion(activeChannel); timeoutCnt = 0; } } } return retval; } float externalInterface_CalculateADCValue(uint8_t channel) { int32_t rawvalue = 0; float retValue = 0.0; if(channel < MAX_ADC_CHANNEL) { rawvalue = ((recBuf[0] << 16) | (recBuf[1] << 8) | (recBuf[2])); switch(recBuf[3] & 0x0C) /* confbyte => Resolution bits*/ { case ADC_RESOLUTION_16BIT: rawvalue = rawvalue >> 8; /* only 2 databytes received shift out confbyte*/ if(rawvalue & (0x1 << (ADC_RESOLUTION_16BIT_VALUE-1))) /* MSB set => negative number */ { rawvalue |= 0xFFFF0000; /* set MSB for int32 */ } else { rawvalue &= 0x0000FFFF; } externalChannel_mV[channel] = ADC_REF_VOLTAGE_MV * 2.0 / (float) pow(2,ADC_RESOLUTION_16BIT_VALUE); /* calculate bit resolution */ break; case ADC_RESOLUTION_18BIT: if(rawvalue & (0x1 << (ADC_RESOLUTION_18BIT_VALUE-1))) /* MSB set => negative number */ { rawvalue |= 0xFFFE0000; /* set MSB for int32 */ } externalChannel_mV[channel] = ADC_REF_VOLTAGE_MV * 2.0 / (float) pow(2,ADC_RESOLUTION_18BIT_VALUE); /* calculate bit resolution */ break; default: rawvalue = 0; break; } externalChannel_mV[channel] = externalChannel_mV[channel] * rawvalue / ADC_GAIN_8_VALUE; retValue = externalChannel_mV[channel]; } return retValue; } float getExternalInterfaceChannel(uint8_t channel) { float retval = 0; if(channel < MAX_ADC_CHANNEL) { retval = externalChannel_mV[channel]; } return retval; }