Diff: AD7124.cpp

Revision:

0:f32d3fb1d3e2

Child:

1:4a4194a5a8ed

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/AD7124.cpp	Mon Oct 24 15:25:58 2016 +0000
@@ -0,0 +1,597 @@
+/**
+*   @file     AD7124.cpp
+*   @brief    Source file for AD7124 ADC
+*   @author   Analog Devices Inc.
+*
+* For support please go to:
+* Github: https://github.com/analogdevicesinc/mbed-adi
+* Support: https://ez.analog.com/community/linux-device-drivers/microcontroller-no-os-drivers
+* Product: http://www.analog.com/ad7124
+* More: https://wiki.analog.com/resources/tools-software/mbed-drivers-all
+
+********************************************************************************
+* Copyright 2016(c) Analog Devices, Inc.
+*
+* All rights reserved.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions are met:
+*  - Redistributions of source code must retain the above copyright
+*    notice, this list of conditions and the following disclaimer.
+*  - Redistributions in binary form must reproduce the above copyright
+*    notice, this list of conditions and the following disclaimer in
+*    the documentation and/or other materials provided with the
+*    distribution.
+*  - Neither the name of Analog Devices, Inc. nor the names of its
+*    contributors may be used to endorse or promote products derived
+*    from this software without specific prior written permission.
+*  - The use of this software may or may not infringe the patent rights
+*    of one or more patent holders.  This license does not release you
+*    from the requirement that you obtain separate licenses from these
+*    patent holders to use this software.
+*  - Use of the software either in source or binary form, must be run
+*    on or directly connected to an Analog Devices Inc. component.
+*
+* THIS SOFTWARE IS PROVIDED BY ANALOG DEVICES "AS IS" AND ANY EXPRESS OR
+* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, NON-INFRINGEMENT,
+* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+* IN NO EVENT SHALL ANALOG DEVICES BE LIABLE FOR ANY DIRECT, INDIRECT,
+* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+* LIMITED TO, INTELLECTUAL PROPERTY RIGHTS, PROCUREMENT OF SUBSTITUTE GOODS OR
+* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*
+********************************************************************************/
+
+#include <stdint.h>
+#include "mbed.h"
+#include "AD7124.h"
+
+/**
+ * @brief AD7790 constructor, sets CS pin and SPI format
+ * @param CS - (optional)chip select of the AD7790
+ * @param MOSI - (optional)pin of the SPI interface
+ * @param MISO - (optional)pin of the SPI interface
+ * @param SCK  - (optional)pin of the SPI interface
+ */
+AD7124::AD7124(PinName CS,
+               PinName MOSI,
+               PinName MISO,
+               PinName SCK) :
+    miso(MISO), ad7124(MOSI, MISO, SCK), cs(CS)
+{
+    cs = true; // cs is active low
+    ad7124.format(8, _SPI_MODE);
+    this->regs = ad7124_regs;
+    this->useCRC = false;
+}
+
+/**
+ * @brief Set AD7790 SPI frequency
+ * @param hz - SPI bus frequency in hz
+ * @return none
+ */
+void AD7124::frequency(int hz)
+{
+    ad7124.frequency(hz);
+}
+
+/**
+ * @brief Resets the AD7790
+ * @return none
+ */
+/*void AD7124::reset()
+{
+    ad7124.format(8, _SPI_MODE);
+    cs = false;
+    wait_us(_DELAY_TIMING);
+    ad7124.write(_RESET);
+    ad7124.write(_RESET);
+    ad7124.write(_RESET);
+    ad7124.write(_RESET);
+    ad7124.write(_RESET);
+    ad7124.write(_RESET);
+    ad7124.write(_RESET);
+    ad7124.write(_RESET);
+    wait_us(_DELAY_TIMING);
+    cs = true;
+    //_continous_conversion = true;
+}*/
+/**
+ * @brief Reads a register of the AD7790
+ * @param  address - address of the register
+ * @return value of the register
+ */
+uint16_t AD7124::read_reg(uint8_t address)
+{
+    uint16_t data = address << 8;
+    data |= _DUMMY_BYTE;
+    data |= _READ_FLAG;
+    return	write_spi(data);
+}
+
+/**
+ * @brief Writes a register of the AD7790
+ * @param address - address of the register
+ * @param reg_val - value to be written
+ * @return none
+ *
+ */
+void AD7124::write_reg(uint8_t address, uint8_t reg_val)
+{
+    uint16_t spi_data = address << 8;
+    spi_data |= reg_val;
+    write_spi(spi_data);
+}
+
+/**
+ * @brief Writes 16bit data to the AD7790 SPI interface
+ * @param reg_val to be written
+ * @return data returned by the AD7790
+ */
+uint16_t AD7124::write_spi(uint16_t reg_val)
+{
+    uint16_t data_result;
+    uint8_t upper_byte = (reg_val >> 8) & 0xFF;
+    uint8_t lower_byte = reg_val & 0xFF;
+    ad7124.format(8, _SPI_MODE);
+    cs = false;
+    data_result  =  (ad7124.write(upper_byte) << 8);
+    data_result |=   ad7124.write(lower_byte);
+    cs = true;
+    return data_result;
+}
+
+
+
+/***************************************************************************//**
+* @brief Reads the value of the specified register without checking if the
+*        device is ready to accept user requests.
+*
+* @param device - The handler of the instance of the driver.
+* @param pReg - Pointer to the register structure holding info about the
+*               register to be read. The read value is stored inside the
+*               register structure.
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::NoCheckReadRegister(ad7124_st_reg* pReg)
+{
+    int32_t ret       = 0;
+    uint8_t buffer[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+    uint8_t i         = 0;
+    uint8_t check8    = 0;
+    uint8_t msgBuf[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+
+
+    check8 = useCRC;
+
+    /* Build the Command word */
+    buffer[0] = AD7124_COMM_REG_WEN | AD7124_COMM_REG_RD |
+                AD7124_COMM_REG_RA(pReg->addr);
+
+    /* Read data from the device */
+    ret = SPI_Read(buffer,
+                   ((useCRC != AD7124_DISABLE_CRC) ? pReg->size + 1
+                    : pReg->size) + 1);
+    if(ret < 0)
+        return ret;
+
+    /* Check the CRC */
+    if(check8 == AD7124_USE_CRC) {
+        msgBuf[0] = AD7124_COMM_REG_WEN | AD7124_COMM_REG_RD |
+                    AD7124_COMM_REG_RA(pReg->addr);
+        for(i = 1; i < pReg->size + 2; ++i) {
+            msgBuf[i] = buffer[i];
+        }
+        check8 = ComputeCRC8(msgBuf, pReg->size + 2);
+    }
+
+    if(check8 != 0) {
+        /* ReadRegister checksum failed. */
+        return COMM_ERR;
+    }
+
+    /* Build the result */
+    pReg->value = 0;
+    for(i = 1; i < pReg->size + 1; i++) {
+        pReg->value <<= 8;
+        pReg->value += buffer[i];
+    }
+
+    return ret;
+}
+
+/***************************************************************************//**
+* @brief Writes the value of the specified register without checking if the
+*        device is ready to accept user requests.
+*
+* @param device - The handler of the instance of the driver.
+* @param reg - Register structure holding info about the register to be written
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::NoCheckWriteRegister(ad7124_st_reg reg)
+{
+    int32_t ret      = 0;
+    int32_t regValue = 0;
+    uint8_t wrBuf[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+    uint8_t i        = 0;
+    uint8_t crc8     = 0;
+
+
+    /* Build the Command word */
+    wrBuf[0] = AD7124_COMM_REG_WEN | AD7124_COMM_REG_WR |
+               AD7124_COMM_REG_RA(reg.addr);
+
+    /* Fill the write buffer */
+    regValue = reg.value;
+    for(i = 0; i < reg.size; i++) {
+        wrBuf[reg.size - i] = regValue & 0xFF;
+        regValue >>= 8;
+    }
+
+    /* Compute the CRC */
+    if(useCRC != AD7124_DISABLE_CRC) {
+        crc8 = ComputeCRC8(wrBuf, reg.size + 1);
+        wrBuf[reg.size + 1] = crc8;
+    }
+
+    /* Write data to the device */
+    ret = SPI_Write(wrBuf,
+                    (useCRC != AD7124_DISABLE_CRC) ? reg.size + 2
+                    : reg.size + 1);
+
+    return ret;
+}
+
+/***************************************************************************//**
+* @brief Reads the value of the specified register only when the device is ready
+*        to accept user requests. If the device ready flag is deactivated the
+*        read operation will be executed without checking the device state.
+*
+* @param device - The handler of the instance of the driver.
+* @param pReg - Pointer to the register structure holding info about the
+*               register to be read. The read value is stored inside the
+*               register structure.
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::ReadRegister(ad7124_st_reg* pReg)
+{
+    int32_t ret;
+
+    if (pReg->addr != ERR_REG && check_ready) {
+        ret = WaitForSpiReady(spi_rdy_poll_cnt);
+        if (ret < 0)
+            return ret;
+    }
+    ret = NoCheckReadRegister(pReg);
+
+    return ret;
+}
+
+/***************************************************************************//**
+* @brief Writes the value of the specified register only when the device is
+*        ready to accept user requests. If the device ready flag is deactivated
+*        the write operation will be executed without checking the device state.
+*
+* @param device - The handler of the instance of the driver.
+* @param reg - Register structure holding info about the register to be written
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::WriteRegister(ad7124_st_reg pReg)
+{
+    int32_t ret;
+
+    if (check_ready) {
+        ret = WaitForSpiReady(spi_rdy_poll_cnt);
+        if (ret < 0)
+            return ret;
+    }
+    ret = NoCheckWriteRegister(pReg);
+
+    return ret;
+}
+
+/***************************************************************************//**
+* @brief Reads and returns the value of a device register. The read value is
+*        also stored in software register list of the device.
+*
+* @param device - The handler of the instance of the driver.
+* @param reg - Which register to read from.
+* @param pError - Pointer to the location where to store the error code if an
+*                 error occurs. Stores 0 for success or negative error code.
+*                 Does not store anything if pErorr = NULL;
+*
+* @return Returns the value read from the specified register.
+*******************************************************************************/
+uint32_t AD7124::ReadDeviceRegister(enum ad7124_registers reg)
+{
+    ReadRegister(&regs[reg]);
+    return (regs[reg].value);
+}
+
+/***************************************************************************//**
+* @brief Writes the specified value to a device register. The value to be
+*        written is also stored in the software register list of the device.
+*
+* @param device - The handler of the instance of the driver.
+* @param reg - Which register to write to.
+* @param value - The value to be written to the reigster of the device.
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::WriteDeviceRegister(enum ad7124_registers reg, uint32_t value)
+{
+    regs[reg].value = value;
+    return(WriteRegister(regs[reg]));
+}
+
+/***************************************************************************//**
+* @brief Resets the device.
+*
+* @param device - The handler of the instance of the driver.
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::Reset()
+{
+    int32_t ret = 0;
+    uint8_t wrBuf[8] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
+
+    ret = SPI_Write( wrBuf, 8);
+
+
+    return ret;
+}
+
+/***************************************************************************//**
+* @brief Waits until the device can accept read and write user actions.
+*
+* @param device - The handler of the instance of the driver.
+* @param timeout - Count representing the number of polls to be done until the
+*                  function returns.
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::WaitForSpiReady(uint32_t timeout)
+{
+    ad7124_st_reg *regs;
+    int32_t ret;
+    int8_t ready = 0;
+
+    regs = this->regs;
+
+    while(!ready && --timeout) {
+        /* Read the value of the Error Register */
+        ret = ReadRegister(&regs[AD7124_Error]);
+        if(ret < 0)
+            return ret;
+
+        /* Check the SPI IGNORE Error bit in the Error Register */
+        ready = (regs[AD7124_Error].value &
+                 AD7124_ERR_REG_SPI_IGNORE_ERR) == 0;
+    }
+
+    return timeout ? 0 : TIMEOUT;
+}
+
+/***************************************************************************//**
+* @brief Waits until a new conversion result is available.
+*
+* @param device - The handler of the instance of the driver.
+* @param timeout - Count representing the number of polls to be done until the
+*                  function returns if no new data is available.
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::WaitForConvReady(uint32_t timeout)
+{
+    ad7124_st_reg *regs;
+    int32_t ret;
+    int8_t ready = 0;
+
+    regs = this->regs;
+
+    while(!ready && --timeout) {
+        /* Read the value of the Status Register */
+        ret = ReadRegister(&regs[AD7124_Status]);
+        if(ret < 0)
+            return ret;
+
+        /* Check the RDY bit in the Status Register */
+        ready = (regs[AD7124_Status].value &
+                 AD7124_STATUS_REG_RDY) == 0;
+        wait_ms(1);
+    }
+
+    return timeout ? 0 : TIMEOUT;
+}
+
+bool AD7124::get_miso()
+{
+    return miso.read();
+}
+
+/***************************************************************************//**
+* @brief Reads the conversion result from the device.
+*
+* @param device - The handler of the instance of the driver.
+* @param pData - Pointer to store the read data.
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::ReadData( int32_t* pData)
+{
+    int32_t ret       = 0;
+    uint8_t check8    = 0;
+    uint8_t buffer[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+    uint8_t i         = 0;
+    uint8_t msgBuf[8] = {0, 0, 0, 0, 0, 0, 0, 0};
+    ad7124_st_reg *pReg;
+
+    if( !pData)
+        return INVALID_VAL;
+
+    pReg = &regs[AD7124_Data];
+
+    /* Build the Command word */
+    buffer[0] = AD7124_COMM_REG_WEN | AD7124_COMM_REG_RD |
+                AD7124_COMM_REG_RA(pReg->addr);
+
+
+    /* Read data from the device */
+    ret = SPI_Read(buffer,
+                   ((useCRC != AD7124_DISABLE_CRC) ? pReg->size + 1
+                    : pReg->size) + 2);
+
+    if(ret < 0)
+        return ret;
+
+    /* Check the CRC */
+    if(check8 == AD7124_USE_CRC) {
+        msgBuf[0] = AD7124_COMM_REG_WEN | AD7124_COMM_REG_RD |
+                    AD7124_COMM_REG_RA(pReg->addr);
+        for(i = 1; i < pReg->size + 2; ++i) {
+            msgBuf[i] = buffer[i];
+        }
+        check8 = ComputeCRC8(msgBuf, pReg->size + 3);
+    }
+
+    if(check8 != 0) {
+        /* ReadRegister checksum failed. */
+        return COMM_ERR;
+    }
+
+    /* Build the result */
+    *pData = 0;
+    for(i = 1; i < pReg->size + 2; i++) {
+        *pData <<= 8;
+        *pData += buffer[i];
+    }
+    wait_ms(500);
+    return ret;
+}
+
+/***************************************************************************//**
+* @brief Computes the CRC checksum for a data buffer.
+*
+* @param pBuf - Data buffer
+* @param bufSize - Data buffer size in bytes
+*
+* @return Returns the computed CRC checksum.
+*******************************************************************************/
+uint8_t AD7124::ComputeCRC8(uint8_t * pBuf, uint8_t bufSize)
+{
+    uint8_t i   = 0;
+    uint8_t crc = 0;
+
+    while(bufSize) {
+        for(i = 0x80; i != 0; i >>= 1) {
+            if(((crc & 0x80) != 0) != ((*pBuf & i) != 0)) { /* MSB of CRC register XOR input Bit from Data */
+                crc <<= 1;
+                crc ^= AD7124_CRC8_POLYNOMIAL_REPRESENTATION;
+            } else {
+                crc <<= 1;
+            }
+        }
+        pBuf++;
+        bufSize--;
+    }
+    return crc;
+}
+
+
+/***************************************************************************//**
+* @brief Updates the device SPI interface settings.
+*
+* @param device - The handler of the instance of the driver.
+*
+* @return None.
+*******************************************************************************/
+void AD7124::UpdateDevSpiSettings()
+{
+    ad7124_st_reg *regs;
+
+    regs = this->regs;
+
+    if (regs[AD7124_Error_En].value & AD7124_ERREN_REG_SPI_IGNORE_ERR_EN) {
+        check_ready = 1;
+    } else {
+        check_ready = 0;
+    }
+}
+
+/***************************************************************************//**
+* @brief Initializes the AD7124.
+*
+* @param device - The handler of the instance of the driver.
+* @param slave_select - The Slave Chip Select Id to be passed to the SPI calls.
+* @param regs - The list of registers of the device (initialized or not) to be
+*               added to the instance of the driver.
+*
+* @return Returns 0 for success or negative error code.
+*******************************************************************************/
+int32_t AD7124::Setup()
+{
+    int32_t ret;
+    uint8_t regNr;
+
+
+    spi_rdy_poll_cnt = 25000;
+
+    /* Initialize the SPI communication. */
+    /*ret = SPI_Init(0, 2500000, 1, 0);
+    if (ret < 0)
+        return ret;*/
+
+    /*  Reset the device interface.*/
+    ret = Reset();
+    if (ret < 0)
+        return ret;
+
+    check_ready = 1;
+
+    /* Initialize registers AD7124_ADC_Control through AD7124_Filter_7. */
+    for(regNr = static_cast<uint8_t>(AD7124_Status); (regNr < static_cast<uint8_t>(AD7124_Offset_0)) && !(ret < 0);
+            regNr++) {
+        if (regs[regNr].rw == AD7124_RW) {
+            ret = WriteRegister(regs[regNr]);
+            if (ret < 0)
+                break;
+        }
+
+        /* Get CRC State and device SPI interface settings */
+        if (regNr == AD7124_Error_En) {
+            UpdateDevSpiSettings();
+        }
+    }
+
+    return ret;
+}
+
+uint8_t AD7124::SPI_Read(uint8_t *data, uint8_t bytes_number)
+{
+    cs = false;
+    for(uint8_t byte = 0; byte < bytes_number; byte++) {
+        data[byte] = ad7124.write(data[byte]);
+    }
+    cs = true;
+    return bytes_number;
+}
+
+uint8_t AD7124::SPI_Write(uint8_t *data, uint8_t bytes_number)
+{
+    cs = false;
+    for(uint8_t byte = 0; byte < bytes_number; byte++) {
+        ad7124.write(data[byte]);
+    }
+
+    cs = true;
+    return bytes_number;
+
+}