Donal Morrissey / MCP4725

Library for controlling an MCP4725 "12-Bit Digital-to-Analog Converter with EEPROM Memory". There is an accompanying test suite program "MCP_4725_Library_Test" that can be used to test this library.

Dependents:   IGGE_Power MCP4725_Library_Test MCP4725 SinWave ... more

mcp4725.h@5:3e6ffce1eea2, 2013-11-07 (annotated)

Committer:
donalm
Date:
Thu Nov 07 19:05:29 2013 +0000
Revision:
5:3e6ffce1eea2
Parent:
4:e0d667c9b23b 
Fixed memory leak.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
donalm 0:3214e3bbf25c 1 #ifndef MCP_4725_H
donalm 0:3214e3bbf25c 2 #define MCP_4725_H
donalm 0:3214e3bbf25c 3
donalm 0:3214e3bbf25c 4 #include "stdbool.h"
donalm 0:3214e3bbf25c 5 #include "mbed.h"
donalm 0:3214e3bbf25c 6 #include "I2C.h"
donalm 0:3214e3bbf25c 7
donalm 0:3214e3bbf25c 8
donalm 0:3214e3bbf25c 9 /** MCP4725 class.
donalm 0:3214e3bbf25c 10 * Used for interfacing with a mcp4725 12-Bit Digital-to-Analog Converter.
donalm 4:e0d667c9b23b 11 * To convert between the 12bit dac_value and Vout, use the following formula: dac_value = (Vout*4096/Vref), where Vout is
donalm 4:e0d667c9b23b 12 * the desired output analog voltage, Vref is the voltage connected to the Vdd pin of the device. Typically Vdd will be 3.3volts.
donalm 3:4488787a216b 13 *
donalm 3:4488787a216b 14 * Note: There is an accompanying test suite program "MCP_4725_Library_Test" that can be used to test this library.
donalm 3:4488787a216b 15 *
donalm 0:3214e3bbf25c 16 */
donalm 0:3214e3bbf25c 17 class MCP4725
donalm 0:3214e3bbf25c 18 {
donalm 0:3214e3bbf25c 19 public:
donalm 0:3214e3bbf25c 20 /** The device supports two types of power modes: normal and power-down. In normal mode the device
donalm 0:3214e3bbf25c 21 * operates a normal digital to analog conversion. In power-down mode all digitial to analog
donalm 0:3214e3bbf25c 22 * conversion is stopped, resulting in the device using less power (typically 60nA). Also, in power
donalm 0:3214e3bbf25c 23 * down mode Vout will be pulled to ground using either a 1k, 100k or 500k ohm internal resistors. */
donalm 0:3214e3bbf25c 24 enum PowerMode {
donalm 0:3214e3bbf25c 25 /** In normal mode the device operates a normal D2A conversion. */
donalm 0:3214e3bbf25c 26 Normal=0,
donalm 0:3214e3bbf25c 27 /** Enter the device into a power down mode, and pull Vout to ground using an internal 1k resistor. */
donalm 0:3214e3bbf25c 28 PowerDown1k=1,
donalm 0:3214e3bbf25c 29 /** Enter the device into a power down mode, and pull Vout to ground using an internal 100k resistor. */
donalm 0:3214e3bbf25c 30 PowerDown100k=2,
donalm 0:3214e3bbf25c 31 /** Enter the device into a power down mode, and pull Vout to ground using an internal 500k resistor. */
donalm 0:3214e3bbf25c 32 PowerDown500k=3
donalm 0:3214e3bbf25c 33 };
donalm 0:3214e3bbf25c 34
donalm 0:3214e3bbf25c 35 /** The device supports 3 different I2C bus frequencies.*/
donalm 0:3214e3bbf25c 36 enum BusFrequency {
donalm 0:3214e3bbf25c 37 /** Standard 100kHz bus. */
donalm 0:3214e3bbf25c 38 Standard100kHz,
donalm 0:3214e3bbf25c 39 /** Fast 400kHz bus. */
donalm 0:3214e3bbf25c 40 Fast400kHz,
donalm 1:e78abc423fb5 41 /** High Speed 3.4Mhz bus. WARNING: the test suite fails for the mbed LPC1768 when this frequency is selected - not tested on other platforms.*/
donalm 0:3214e3bbf25c 42 HighSpeed3_4Mhz
donalm 0:3214e3bbf25c 43 };
donalm 0:3214e3bbf25c 44
donalm 0:3214e3bbf25c 45 /** Create an mcp4725 I2C interface
donalm 0:3214e3bbf25c 46 *
donalm 0:3214e3bbf25c 47 * @param sda I2C data line pin
donalm 0:3214e3bbf25c 48 * @param scl I2C clock line pin
donalm 0:3214e3bbf25c 49 * @param bus_frequency the frequency at which the I2C bus is running.
donalm 0:3214e3bbf25c 50 * @param device_address_bits The 3bit address bits of the device.
donalm 0:3214e3bbf25c 51 */
donalm 0:3214e3bbf25c 52 MCP4725(PinName sda, PinName scl, BusFrequency bus_frequency, int device_address_bits);
donalm 0:3214e3bbf25c 53
donalm 0:3214e3bbf25c 54
donalm 0:3214e3bbf25c 55 /* Update the power mode and DAC value.
donalm 0:3214e3bbf25c 56 *
donalm 0:3214e3bbf25c 57 * @param mode The Power mode to set the device into.
donalm 0:3214e3bbf25c 58 * @param dac_value The 12bit dac register data value.
donalm 0:3214e3bbf25c 59 * @param writeToEeprom True if the config is to be stored
donalm 0:3214e3bbf25c 60 * in eeprom, otherwise false
donalm 0:3214e3bbf25c 61 *
donalm 0:3214e3bbf25c 62 * @returns
donalm 0:3214e3bbf25c 63 * 0 on success,
donalm 0:3214e3bbf25c 64 * non-0 on failure
donalm 0:3214e3bbf25c 65 */
donalm 0:3214e3bbf25c 66 int write(enum PowerMode mode, int dac_value, bool writeToEeprom);
donalm 0:3214e3bbf25c 67
donalm 0:3214e3bbf25c 68
donalm 0:3214e3bbf25c 69 /** Read the contents of the dac register, the contents of eeprom, and if an eeprom write is currently active.
donalm 0:3214e3bbf25c 70 *
donalm 0:3214e3bbf25c 71 * @param mode Pointer to variable to store the current power mode.
donalm 0:3214e3bbf25c 72 * @param mode_eeprom Pointer to variable to store the power mode as is stored in eeprom.
donalm 0:3214e3bbf25c 73 * @param dac_value Pointer to variable to store the current dac value.
donalm 0:3214e3bbf25c 74 * @param dac_value_eeprom Pointer to variable to store the dac value as is stored in eeprom.
donalm 0:3214e3bbf25c 75 * @param eeprom_write_in_progress Pointer to variable to store the current eeprom write status.
donalm 0:3214e3bbf25c 76 *
donalm 0:3214e3bbf25c 77 * @returns
donalm 0:3214e3bbf25c 78 * 0 on success,
donalm 0:3214e3bbf25c 79 * non-0 on failure
donalm 0:3214e3bbf25c 80 */
donalm 0:3214e3bbf25c 81 int read(enum PowerMode* mode, enum PowerMode* mode_eeprom, int* dac_value, int* dac_value_eeprom, bool* eeprom_write_in_progress);
donalm 0:3214e3bbf25c 82
donalm 0:3214e3bbf25c 83 protected:
donalm 0:3214e3bbf25c 84 /** mbed I2C interface driver. */
donalm 5:3e6ffce1eea2 85 I2C _i2c_interface;
donalm 0:3214e3bbf25c 86 /** The full i2c device address. */
donalm 0:3214e3bbf25c 87 int _device_address;
donalm 0:3214e3bbf25c 88
donalm 0:3214e3bbf25c 89 };
donalm 0:3214e3bbf25c 90
donalm 0:3214e3bbf25c 91 #endif