SCH MME NIBP ref. code

Dependencies:   Adafruit_GFX

Revision:
0:8edd7b830280
Child:
1:63bc0088a8ed
diff -r 000000000000 -r 8edd7b830280 ADS1115.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ADS1115.h	Mon Nov 09 00:33:42 2020 +0000
@@ -0,0 +1,169 @@
+#include <mbed.h>
+
+/*=========================================================================
+    I2C ADDRESS/BITS
+    -----------------------------------------------------------------------*/
+    #define ADS1115_ADDRESS                 (0x49)    // 100 1001 (ADDR = VDD)
+/*=========================================================================*/
+
+/*=========================================================================
+    CONVERSION DELAY (in mS)
+    -----------------------------------------------------------------------*/
+    #define ADS1115_CONVERSIONDELAY         (8)
+/*=========================================================================*/
+
+/*=========================================================================
+    POINTER REGISTER
+    -----------------------------------------------------------------------*/
+    #define ADS1115_REG_POINTER_MASK        (0x03)
+    #define ADS1115_REG_POINTER_CONVERT     (0x00)
+    #define ADS1115_REG_POINTER_CONFIG      (0x01)
+    #define ADS1115_REG_POINTER_LOWTHRESH   (0x02)
+    #define ADS1115_REG_POINTER_HITHRESH    (0x03)
+/*=========================================================================*/
+
+/*=========================================================================
+    CONFIG REGISTER
+    -----------------------------------------------------------------------*/
+    #define ADS1115_REG_CONFIG_OS_MASK      (0x8000)
+    #define ADS1115_REG_CONFIG_OS_SINGLE    (0x8000)  // Write: Set to start a single-conversion
+    #define ADS1115_REG_CONFIG_OS_BUSY      (0x0000)  // Read: Bit = 0 when conversion is in progress
+    #define ADS1115_REG_CONFIG_OS_NOTBUSY   (0x8000)  // Read: Bit = 1 when device is not performing a conversion
+
+    #define ADS1115_REG_CONFIG_MUX_MASK     (0x7000)
+    #define ADS1115_REG_CONFIG_MUX_DIFF_0_1 (0x0000)  // Differential P = AIN0, N = AIN1 (default)
+    #define ADS1115_REG_CONFIG_MUX_DIFF_0_3 (0x1000)  // Differential P = AIN0, N = AIN3
+    #define ADS1115_REG_CONFIG_MUX_DIFF_1_3 (0x2000)  // Differential P = AIN1, N = AIN3
+    #define ADS1115_REG_CONFIG_MUX_DIFF_2_3 (0x3000)  // Differential P = AIN2, N = AIN3
+    #define ADS1115_REG_CONFIG_MUX_SINGLE_0 (0x4000)  // Single-ended AIN0
+    #define ADS1115_REG_CONFIG_MUX_SINGLE_1 (0x5000)  // Single-ended AIN1
+    #define ADS1115_REG_CONFIG_MUX_SINGLE_2 (0x6000)  // Single-ended AIN2
+    #define ADS1115_REG_CONFIG_MUX_SINGLE_3 (0x7000)  // Single-ended AIN3
+
+    #define ADS1115_REG_CONFIG_PGA_MASK     (0x0E00)
+    #define ADS1115_REG_CONFIG_PGA_6_144V   (0x0000)  // +/-6.144V range = Gain 2/3
+    #define ADS1115_REG_CONFIG_PGA_4_096V   (0x0200)  // +/-4.096V range = Gain 1
+    #define ADS1115_REG_CONFIG_PGA_2_048V   (0x0400)  // +/-2.048V range = Gain 2 (default)
+    #define ADS1115_REG_CONFIG_PGA_1_024V   (0x0600)  // +/-1.024V range = Gain 4
+    #define ADS1115_REG_CONFIG_PGA_0_512V   (0x0800)  // +/-0.512V range = Gain 8
+    #define ADS1115_REG_CONFIG_PGA_0_256V   (0x0A00)  // +/-0.256V range = Gain 16
+
+    #define ADS1115_REG_CONFIG_MODE_MASK    (0x0100)
+    #define ADS1115_REG_CONFIG_MODE_CONTIN  (0x0000)  // Continuous conversion mode
+    #define ADS1115_REG_CONFIG_MODE_SINGLE  (0x0100)  // Power-down single-shot mode (default)
+
+    #define ADS1115_REG_CONFIG_DR_MASK      (0x00E0)  
+    #define ADS1115_REG_CONFIG_DR_8SPS    (0x0000)  // 8SPS
+    #define ADS1115_REG_CONFIG_DR_16SPS    (0x0020)  // 16SPS
+    #define ADS1115_REG_CONFIG_DR_32SPS    (0x0040)  // 32SPS
+    #define ADS1115_REG_CONFIG_DR_64SPS    (0x0060)  // 64SPS
+    #define ADS1115_REG_CONFIG_DR_128SPS   (0x0080)  // 128SPS (default)
+    #define ADS1115_REG_CONFIG_DR_475SPS   (0x00A0)  // 475SPS
+    #define ADS1115_REG_CONFIG_DR_860SPS   (0x00C0)  // 860SPS
+
+    #define ADS1115_REG_CONFIG_CMODE_MASK   (0x0010)
+    #define ADS1115_REG_CONFIG_CMODE_TRAD   (0x0000)  // Traditional comparator with hysteresis (default)
+    #define ADS1115_REG_CONFIG_CMODE_WINDOW (0x0010)  // Window comparator
+
+    #define ADS1115_REG_CONFIG_CPOL_MASK    (0x0008)
+    #define ADS1115_REG_CONFIG_CPOL_ACTVLOW (0x0000)  // ALERT/RDY pin is low when active (default)
+    #define ADS1115_REG_CONFIG_CPOL_ACTVHI  (0x0008)  // ALERT/RDY pin is high when active
+
+    #define ADS1115_REG_CONFIG_CLAT_MASK    (0x0004)  // Determines if ALERT/RDY pin latches once asserted
+    #define ADS1115_REG_CONFIG_CLAT_NONLAT  (0x0000)  // Non-latching comparator (default)
+    #define ADS1115_REG_CONFIG_CLAT_LATCH   (0x0004)  // Latching comparator
+
+    #define ADS1115_REG_CONFIG_CQUE_MASK    (0x0003)
+    #define ADS1115_REG_CONFIG_CQUE_1CONV   (0x0000)  // Assert ALERT/RDY after one conversions
+    #define ADS1115_REG_CONFIG_CQUE_2CONV   (0x0001)  // Assert ALERT/RDY after two conversions
+    #define ADS1115_REG_CONFIG_CQUE_4CONV   (0x0002)  // Assert ALERT/RDY after four conversions
+    #define ADS1115_REG_CONFIG_CQUE_NONE    (0x0003)  // Disable the comparator and put ALERT/RDY in high state (default)
+/*=========================================================================*/
+
+typedef enum {
+    GAIN_TWOTHIRDS    = ADS1115_REG_CONFIG_PGA_6_144V,
+    GAIN_ONE          = ADS1115_REG_CONFIG_PGA_4_096V,
+    GAIN_TWO          = ADS1115_REG_CONFIG_PGA_2_048V,
+    GAIN_FOUR         = ADS1115_REG_CONFIG_PGA_1_024V,
+    GAIN_EIGHT        = ADS1115_REG_CONFIG_PGA_0_512V,
+    GAIN_SIXTEEN      = ADS1115_REG_CONFIG_PGA_0_256V
+} adsGain_t;
+
+uint8_t   m_i2cAddress;
+uint8_t   m_conversionDelay;
+uint8_t   m_bitShift;
+adsGain_t m_gain;
+I2C*      m_i2c;
+
+void ADS1115_Init(I2C* i2c, uint8_t i2cAddress)
+{
+    // shift 7 bit address 1 left: read expects 8 bit address, see I2C.h
+    m_i2cAddress = i2cAddress << 1;
+    m_conversionDelay = ADS1115_CONVERSIONDELAY;
+    m_gain = GAIN_TWOTHIRDS; /* +/- 6.144V range (limited to VDD +0.3V max!) */
+    m_i2c = i2c;
+}
+
+uint16_t ADS1115_readRegister(uint8_t i2cAddress, uint8_t reg)
+{
+    char data[2];
+    data[0] = reg; // temporary use this to send address to conversion register
+    m_i2c->write(i2cAddress, data, 1);
+    m_i2c->read(i2cAddress, data, 2);
+    return (data[0] << 8 | data [1]);
+}
+
+void ADS1115_writeRegister(uint8_t i2cAddress, uint8_t reg, uint16_t value)
+{
+    char cmd[3];
+    cmd[0] = (char)reg;
+    cmd[1] = (char)(value>>8);
+    cmd[2] = (char)(value & 0xFF);
+    m_i2c->write(i2cAddress, cmd, 3);
+}
+
+
+uint16_t ADS1115_setConti_ADC_SingleEnded(uint8_t channel)
+{
+    if (channel > 3) {
+        return 0;
+    }
+
+    // Start with default values
+    uint16_t config = ADS1115_REG_CONFIG_CQUE_1CONV   | // Assert ALERT/RDY after one conversions
+                      ADS1115_REG_CONFIG_CLAT_NONLAT  | // Non-latching (default val)
+                      ADS1115_REG_CONFIG_CPOL_ACTVLOW | // Alert/Rdy active low   (default val)
+                      ADS1115_REG_CONFIG_CMODE_TRAD   | // Traditional comparator (default val)
+                      ADS1115_REG_CONFIG_DR_475SPS    | // 475SPS
+                      ADS1115_REG_CONFIG_MODE_CONTIN;   // Countinuous-conversion mode 
+
+    // Set PGA/voltage range
+    config |= m_gain;
+
+    // Set single-ended input channel
+    switch (channel) {
+        case (0):
+            config |= ADS1115_REG_CONFIG_MUX_SINGLE_0;
+            break;
+        case (1):
+            config |= ADS1115_REG_CONFIG_MUX_SINGLE_1;
+            break;
+        case (2):
+            config |= ADS1115_REG_CONFIG_MUX_SINGLE_2;
+            break;
+        case (3):
+            config |= ADS1115_REG_CONFIG_MUX_SINGLE_3;
+            break;
+    }   
+    ADS1115_writeRegister(m_i2cAddress, ADS1115_REG_POINTER_LOWTHRESH, 0x7fff);
+    ADS1115_writeRegister(m_i2cAddress, ADS1115_REG_POINTER_HITHRESH, 0x8000);
+    ADS1115_writeRegister(m_i2cAddress, ADS1115_REG_POINTER_CONFIG, config);
+    
+    return 0;
+}
+
+int16_t ADS1115_getConti_ADC_SingleEnded()
+{
+    uint16_t res = ADS1115_readRegister(m_i2cAddress, ADS1115_REG_POINTER_CONVERT);
+    return (int16_t)res;
+}
\ No newline at end of file