Library Description

Library can communicate with the device via SPI driver by writting to the registers and reading from the registers. Library offers a choice to measure output voltage and current, depending on the input voltage supply, and can measure power by calculating this two data values. Library also can check the output state from modulator for both channels. The data resolution can be changed to 16, 24, and 32-bit. For more details check documentation.

Key functions:

• uint8_t pwrmeter2_writeReg( uint8_t register_address, uint32_t transfer_data ) - Function writes 24-bit data to the register.
• uint8_t pwrmeter2_readReg( uint8_t register_address, uint32_t *dataOut, uint8_t nData ) - Function reads the desired number of 24-bit data from the register/registers.
• uint8_t pwrmeter2_readConvData( uint32_t *dataCH0, uint32_t *dataCH1 ) - Function reads the converted data from both channels when conversion is finished.
• void pwrmeter2_getData( int32_t *voltageData, int32_t *currentData, int32_t *powerData ) - Function gets the calculated voltage(mV), current(mA) and power(mW) data.

Example description

The application is composed of three sections :

System Initialization - Initializes peripherals and pins.
Application Initialization - Initializes SPI driver and performs the hardware reset of the device.
Also performs the device configuration and gain calibration for both channels, for the properly working.
Application Task - (code snippet) - Gets calculated voltage, current and power data every 500 miliseconds
and shows results on UART.

void applicationTask()
{
 pwrmeter2_getData( &voltageRes, ¤tRes, &powerRes );

 LongToStr( voltageRes, text );
 mikrobus_logWrite( "U = ", _LOG_TEXT );
 mikrobus_logWrite( text, _LOG_TEXT );
 mikrobus_logWrite( " mV", _LOG_LINE );

 LongToStr( currentRes, text );
 mikrobus_logWrite( "I = ", _LOG_TEXT );
 mikrobus_logWrite( text, _LOG_TEXT );
 mikrobus_logWrite( " mA", _LOG_LINE );

 LongToStr( powerRes, text );
 mikrobus_logWrite( "P = ", _LOG_TEXT );
 mikrobus_logWrite( text, _LOG_TEXT );
 mikrobus_logWrite( " mW", _LOG_LINE );
 mikrobus_logWrite( "", _LOG_LINE );

 Delay_ms( 500 );
}

Other MikroElektronika libraries used in the example:

• SPI
• UART
• Conversions

Additional notes and information

Depending on the development board you are using, you may need USB UART click, USB UART 2 click or RS232 click to connect to your PC, for development systems with no UART to USB interface available on the board. The terminal available in all MikroElektronika compilers, or any other terminal application of your choice, can be used to read the message.