1+ /* !
2+ * @file WipperSnapper_I2C_Driver_MCP3421.h
3+ *
4+ * Device driver for the MCP3421 18-bit ADC sensor.
5+ *
6+ * Adafruit invests time and resources providing this open source code,
7+ * please support Adafruit and open-source hardware by purchasing
8+ * products from Adafruit!
9+ *
10+ * Copyright (c) Tyeth Gundry 2024 for Adafruit Industries.
11+ *
12+ * MIT license, all text here must be included in any redistribution.
13+ *
14+ */
15+ #ifndef WipperSnapper_I2C_Driver_MCP3421_H
16+ #define WipperSnapper_I2C_Driver_MCP3421_H
17+
18+ #include " WipperSnapper_I2C_Driver.h"
19+ #include " Wippersnapper.h"
20+ #include < Adafruit_MCP3421.h>
21+
22+ /* *************************************************************************/
23+ /* !
24+ @brief Class that provides a driver interface for a MCP3421 sensor.
25+ */
26+ /* *************************************************************************/
27+ class WipperSnapper_I2C_Driver_MCP3421 : public WipperSnapper_I2C_Driver {
28+ public:
29+ /* ******************************************************************************/
30+ /* !
31+ @brief Constructor for the MCP3421 sensor.
32+ @param i2c
33+ The I2C interface.
34+ @param sensorAddress
35+ 7-bit device address.
36+ */
37+ /* ******************************************************************************/
38+ WipperSnapper_I2C_Driver_MCP3421 (TwoWire *i2c, uint16_t sensorAddress)
39+ : WipperSnapper_I2C_Driver(i2c, sensorAddress) {
40+ _i2c = i2c;
41+ _sensorAddress = sensorAddress;
42+ }
43+
44+ /* ******************************************************************************/
45+ /* !
46+ @brief Destructor for an MCP3421 sensor.
47+ */
48+ /* ******************************************************************************/
49+ ~WipperSnapper_I2C_Driver_MCP3421 () {
50+ // Called when a MCP3421 component is deleted.
51+ delete _mcp3421;
52+ }
53+
54+ /* ******************************************************************************/
55+ /* !
56+ @brief Initializes the MCP3421 sensor and begins I2C.
57+ @returns True if initialized successfully, False otherwise.
58+ */
59+ /* ******************************************************************************/
60+ bool begin () {
61+ _mcp3421 = new Adafruit_MCP3421 ();
62+ if (_mcp3421->begin ((uint8_t )_sensorAddress, _i2c)) {
63+ WS_DEBUG_PRINTLN (" Failed to find MCP3421 chip"
64+ return false ;
65+ }
66+
67+ // NOTE: We should allow the gain to be set in future, like resolution
68+ // 12_BIT (240 SPS), 14_BIT (60 SPS), 16_BIT (15 SPS), 18_BIT (3.75 SPS)
69+ _mcp3421->setResolution (RESOLUTION_18_BIT);
70+ if (_mcp3421->getResolution () != RESOLUTION_18_BIT) {
71+ WS_DEBUG_PRINTLN (" Failed to set resolution"
72+ return false ;
73+ }
74+
75+ _mcp3421->setMode (MODE_ONE_SHOT);
76+ if (_mcp3421->getMode () != MODE_ONE_SHOT) {
77+ WS_DEBUG_PRINTLN (" Failed to set mode"
78+ return false ;
79+ }
80+ return true ;
81+ }
82+
83+ /* ******************************************************************************/
84+ /* !
85+ @brief Reads a voltage sensor and converts the
86+ reading into the expected SI unit.
87+ @param voltageEvent
88+ voltage sensor reading, in volts.
89+ @returns True if the sensor event was obtained successfully, False
90+ otherwise.
91+ */
92+ /* ******************************************************************************/
93+ bool getEventVoltage (sensors_event_t *voltageEvent) {
94+ ulong start = millis ();
95+ if (!_mcp3421->startOneShotConversion ()) {
96+ WS_DEBUG_PRINTLN (" Failed to start one-shot conversion"
97+ return false ;
98+ }
99+ while (!_mcp3421->isReady ()) {
100+ if (millis () - start > 1000 ) {
101+ WS_DEBUG_PRINTLN (" Timeout waiting for conversion to complete"
102+ return false ;
103+ }
104+ }
105+ voltageEvent->voltage = (float )_mcp3421->readADC ();
106+ return true ;
107+ }
108+
109+ protected:
110+ Adafruit_MCP3421 *_mcp3421; // /< Pointer to MCP3421 temperature sensor object
111+ };
112+
113+ #endif // WipperSnapper_I2C_Driver_MCP3421
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