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Fork of MCP4725_Library_Test by
main.cpp
- Committer:
- donalm
- Date:
- 2013-11-03
- Revision:
- 4:092580187b59
- Parent:
- 0:3e143a2e21c8
- Child:
- 5:03662d049f69
File content as of revision 4:092580187b59:
#include <stdbool.h> #include "mbed.h" #include "mcp4725.h" /** * A test suite for the MCP4725 DAC Library. This Test Application requires the following: * * An MCP4725 connected to the IC2 bus of the mbed LPC1768. * * The analog out of the MCP1768 connected to Pin15 (analog in) of the mbed LPC1768. * * An optional LED & resistor connected to analog output for visual feedback of the running tests. * * This application tests the MCP4725 library's setting of the MCP4725's internal registers (inclusing eeprom storage), * it's analog output and power modes. * */ DigitalOut testLed(LED1); Serial pc(USBTX, USBRX); AnalogIn analogIn(p15); void test_mcp4725_library(PinName sda, PinName scl, MCP4725::BusFrequency bus_frequency, int device_address_bits, char* testName); int test_init(MCP4725* interface, char* testName); int test_simple_read_write_no_eeprom(MCP4725* interface, enum MCP4725::PowerMode mode, float output_voltage); int test_simple_read_write_with_eeprom(MCP4725* interface, enum MCP4725::PowerMode mode, float output_voltage); int test_eeprom_write_status(MCP4725* interface); int main() { pc.printf("Application for testing the MCP4725 interface library\r\n"); test_mcp4725_library(p9, p10, MCP4725::Standard100kHz, 0, "p9, p10, MCP4725::Standard100kHz"); test_mcp4725_library(p9, p10, MCP4725::Fast400kHz, 0, "p9, p10, MCP4725::Fast400kHz"); test_mcp4725_library(p9, p10, MCP4725::HighSpeed3_4Mhz, 0, "p9, p10, MCP4725::HighSpeed3_4Mhz"); while(1) { testLed = 1; wait(0.5); testLed = 0; wait(0.5); } } /** Run a set of simple tests on the mcp4725 driver. * * @param sda I2C data line pin * @param scl I2C clock line pin * @param bus_frequency the frequency at which the I2C bus is running. * @param device_address_bits The 3bit address bits of the device. */ void test_mcp4725_library(PinName sda, PinName scl, MCP4725::BusFrequency bus_frequency, int device_address_bits, char* testName) { //Create our instance of the interface for test MCP4725 mcp4725_interface(sda, scl, bus_frequency, device_address_bits); if(test_init(&mcp4725_interface, testName) == 0) { test_simple_read_write_no_eeprom(&mcp4725_interface, MCP4725::Normal, 3.0); test_simple_read_write_no_eeprom(&mcp4725_interface, MCP4725::PowerDown1k, 1.3); test_simple_read_write_no_eeprom(&mcp4725_interface, MCP4725::PowerDown100k, 1.8); test_simple_read_write_no_eeprom(&mcp4725_interface, MCP4725::PowerDown500k, 0.5); test_simple_read_write_no_eeprom(&mcp4725_interface, MCP4725::Normal, 2.5); test_simple_read_write_with_eeprom(&mcp4725_interface, MCP4725::Normal, 3.0); test_simple_read_write_with_eeprom(&mcp4725_interface, MCP4725::PowerDown1k, 1.3); test_simple_read_write_with_eeprom(&mcp4725_interface, MCP4725::PowerDown100k, 1.8); test_simple_read_write_with_eeprom(&mcp4725_interface, MCP4725::PowerDown500k, 0.5); test_simple_read_write_with_eeprom(&mcp4725_interface, MCP4725::Normal, 2.5); test_eeprom_write_status(&mcp4725_interface); } } /** Initialise the device registers & eeprom. */ int test_init(MCP4725* interface, char* testName) { int result; pc.printf("Initialising test '%s': ", testName); //Prime the device, including its eeprom. result = interface->write(MCP4725::Normal, 0, true); if(result == 0) { wait(0.5); pc.printf("OK\r\n"); } else { pc.printf("FAILED: %d\r\n", result); } return result; } /* Run a simple read/write test that does not write to eeprom. */ int test_simple_read_write_no_eeprom(MCP4725* interface, enum MCP4725::PowerMode mode, float output_voltage) { enum MCP4725::PowerMode read_mode; enum MCP4725::PowerMode read_mode_eeprom;//, write_mode_eeprom; int read_dac_value; int read_dac_value_eeprom;//, write_dac_value_eeprom; bool read_eeprom_write_in_progress; int dac_value = (int) (0xFFF * (output_voltage/3.3) ); pc.printf("\tRead/write test without write to eeprom: "); interface->write(mode, dac_value, false); interface->read(&read_mode, &read_mode_eeprom, &read_dac_value, &read_dac_value_eeprom, &read_eeprom_write_in_progress); if( (mode != read_mode) || (dac_value != read_dac_value) || (read_eeprom_write_in_progress == true) || (read_dac_value == read_dac_value_eeprom) ) { pc.printf("Failed - mode=%d, read_mode=%d, dac_value=%d, read_dac_value=%d, eeprom_write_state:%d\r\n", (int)mode, (int)read_mode, dac_value, read_dac_value, read_eeprom_write_in_progress); return 1; } else { // We need to wait a short period for the output to stabalise. wait(0.2); /* We check at mV resolution. * Resolution of 12bit DAC is 0.8mV * Resolution of 16bit ADC is 0.05mV */ int read_value_mv = (analogIn.read() * 3.3) * 100; int set_value_mv = ((int)(output_voltage*100)); if( (mode == MCP4725::Normal) && (read_value_mv != set_value_mv) ) { pc.printf("Failed: set_value=%dmV, read_value=%dmV\r\n", read_value_mv, set_value_mv); return 1; } else if ( (mode != MCP4725::Normal) && (read_value_mv != 0) ) { pc.printf("Failed: read_value=%dmV, but DAC in PowerDown!\r\n", read_value_mv); return 1; } else { pc.printf("Passed\r\n"); return 0; } } } /* Run a simple read/write test that does write to eeprom. */ int test_simple_read_write_with_eeprom(MCP4725* interface, enum MCP4725::PowerMode mode, float output_voltage) { enum MCP4725::PowerMode read_mode; enum MCP4725::PowerMode read_mode_eeprom;//, write_mode_eeprom; int read_dac_value; int read_dac_value_eeprom;//, write_dac_value_eeprom; bool read_eeprom_write_in_progress; int dac_value = (int) (0xFFF * (output_voltage/3.3) ); pc.printf("\tRead/write test with write to eeprom: "); interface->write(mode, dac_value, true); wait(0.5); //Wait a short period for the eeprom write to complete. interface->read(&read_mode, &read_mode_eeprom, &read_dac_value, &read_dac_value_eeprom, &read_eeprom_write_in_progress); if( (mode != read_mode) || (dac_value != read_dac_value) || (read_eeprom_write_in_progress == true) || (read_dac_value != read_dac_value_eeprom) || (read_mode != read_mode_eeprom) ) { pc.printf("Failed - mode=%d, read_mode=%d, dac_value=%d, read_dac_value=%d, eeprom_write_state:%d\r\n", (int)mode, (int)read_mode, dac_value, read_dac_value, read_eeprom_write_in_progress); return 1; } else { pc.printf("Passed\r\n"); return 0; } } /** Test to see if the eeprom write status bit is reported correctly. */ int test_eeprom_write_status(MCP4725* interface) { enum MCP4725::PowerMode read_mode; enum MCP4725::PowerMode read_mode_eeprom;//, write_mode_eeprom; int read_dac_value; int read_dac_value_eeprom;//, write_dac_value_eeprom; bool read_eeprom_write_in_progress; pc.printf("\tTest eeprom write status: "); interface->write(MCP4725::Normal, 4095, true); //Immediately read the device interface->read(&read_mode, &read_mode_eeprom, &read_dac_value, &read_dac_value_eeprom, &read_eeprom_write_in_progress); if( read_eeprom_write_in_progress == false ) { pc.printf("Failed - EEPROM Write not reported as in progress.\r\n"); return 1; } else { wait(0.5); //Wait a short period for the eeprom write to complete. interface->read(&read_mode, &read_mode_eeprom, &read_dac_value, &read_dac_value_eeprom, &read_eeprom_write_in_progress); if( read_eeprom_write_in_progress == false ) { pc.printf("Passed\r\n"); return 0; } else { pc.printf("Failed - EEPROM Write reported as still in progress.\r\n"); return 1; } } }