Intermediate
30 min

Achieve efficient transmission of analog information in digital systems with ADC1283 and PIC32MX534F064H

Revolutionize data acquisition

ADC 21 Click with PIC32MX clicker

Published Jun 02, 2023

Click board™

ADC 21 Click

Dev Board

PIC32MX clicker

Compiler

NECTO Studio

MCU

PIC32MX534F064H

Ready to take on even the most demanding designs? Our high-performance ADC is up to the challenge!

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Hardware Overview

How does it work?

ADC 21 Click is based on the ADC1283, a high-performance eight-channel analog-to-digital converter from STMicroelectronics. The ADC1283 implements a successive approximation register (SAR) structure to convert analog signals into 12-bit pure binary digital outputs. The conversion circuit includes a fast settling time comparator to convey instruction into the register to store digital 0 or 1 and a redistribution DAC with logic control to have the ADC compare the track signal with a reference signal at each clock cycle. ADC 21 Click communicates with MCU through a standard SPI interface and operates at clock rates up to 3.2MHz,

for all configurations and acquiring conversion results. The AD conversion is carried out in two phases. The sampling phase conveys the input signal through the capacitance array for the first three clock cycles, and then, the evaluation phase performs the conversion into a digital 12-bit signal within 13 clock cycles. At each clock cycle of the evaluation phase, the hold signal is compared with a new value distributed by the DAC, and the result is stored in the 12-bit register, with MSB first. A complete conversion requires 16 clock cycles to generate a new 12-bit word on the SDO pin on the mikroBUS™ socket. This Click board™ can operate with

either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. Additionally, there is a possibility for the ADC1283 analog power supply selection via jumper labeled AVCC SEL to supply the ADC1283 from an external power supply, in the range from 2.7V to 5.5V or with mikroBUS™ power rails. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

ADC 21 Click hardware overview image

Features overview

Development board

PIC32MX Clicker is a compact starter development board that brings the flexibility of add-on Click boards™ to your favorite microcontroller, making it a perfect starter kit for implementing your ideas. It comes with an onboard 32-bit PIC32 microcontroller, the PIC32MX534F064H from Microchip, a USB connector, LED indicators, buttons, a mikroProg connector, and a header for interfacing with external electronics. Thanks to its compact design with clear and easy-recognizable silkscreen markings, it provides a fluid and immersive working experience, allowing access

anywhere and under any circumstances. Each part of the PIC32MX Clicker development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the PIC32MX Clicker programming method, using USB HID mikroBootloader, or through an external mikroProg connector for PIC, dsPIC, or PIC32 programmer, the Clicker board also includes a clean and regulated power supply module for the development kit. The USB Mini-B connection can provide up to 500mA of current, which is more

than enough to operate all onboard and additional modules. All communication methods that mikroBUS™ itself supports are on this board, including the well-established mikroBUS™ socket, reset button, and several buttons and LED indicators. PIC32MX Clicker is an integral part of the Mikroe ecosystem, allowing you to create a new application in minutes. Natively supported by Mikroe software tools, it covers many aspects of prototyping thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

PIC32MX clicker double side image

Microcontroller Overview

MCU Card / MCU

default

Architecture

PIC32

MCU Memory (KB)

64

Silicon Vendor

Microchip

Pin count

64

RAM (Bytes)

16384

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
SPI Chip Select
RG9
CS
SPI Clock
RG6
SCK
SPI Data OUT
RG7
MISO
SPI Data IN
RG8
MOSI
Power Supply
3.3V
3.3V
Ground
GND
GND
NC
NC
PWM
NC
NC
INT
NC
NC
TX
NC
NC
RX
NC
NC
SCL
NC
NC
SDA
Power Supply
5V
5V
Ground
GND
GND
1

Take a closer look

Schematic

ADC 21 Click Schematic schematic

Step by step

Project assembly

PIC clicker front image hardware assembly

Start by selecting your development board and Click board™. Begin with the PIC32MX clicker as your development board.

PIC clicker front image hardware assembly
GNSS2 Click front image hardware assembly
Prog-cut hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
Mini B Connector Clicker Access - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
Necto image step 5 hardware assembly
Necto image step 6 hardware assembly
Necto_MCU_Select_PICPLC16 hardware assembly
Necto No Display image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Debug Image Necto Step hardware assembly

Track your results in real time

Application Output

After loading the code example, pressing the "DEBUG" button builds and programs it on the selected setup.

Application Output Step 1

After programming is completed, a header with buttons for various actions available in the IDE appears. By clicking the green "PLAY "button, we start reading the results achieved with Click board™.

Application Output Step 3

Upon completion of programming, the Application Output tab is automatically opened, where the achieved result can be read. In case of an inability to perform the Debug function, check if a proper connection between the MCU used by the setup and the CODEGRIP programmer has been established. A detailed explanation of the CODEGRIP-board connection can be found in the CODEGRIP User Manual. Please find it in the RESOURCES section.

Application Output Step 4

Software Support

Library Description

This library contains API for ADC 21 Click driver.

Key functions:

  • adc21_read_raw_adc This function reads raw ADC value from the selected channel by using SPI serial interface.

  • adc21_read_voltage This function reads raw ADC value from the selected channel and converts it to proportional voltage level depending on the AVCC selection.

Open Source

Code example

This example can be found in NECTO Studio. Feel free to download the code, or you can copy the code below.

/*!
 * @file main.c
 * @brief ADC 21 Click example
 *
 * # Description
 * This example demonstrates the use of ADC 21 click board by reading and displaying
 * the voltage levels from 8 analog input channels.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes the driver and logger.
 *
 * ## Application Task
 * Reads the voltage levels from all 8 analog input channels and displays the results
 * on the USB UART once per second approximately.
 *
 * @author Stefan Filipovic
 *
 */

#include "board.h"
#include "log.h"
#include "adc21.h"

static adc21_t adc21;
static log_t logger;

void application_init ( void )
{
    log_cfg_t log_cfg;  /**< Logger config object. */
    adc21_cfg_t adc21_cfg;  /**< Click config object. */

    /** 
     * Logger initialization.
     * Default baud rate: 115200
     * Default log level: LOG_LEVEL_DEBUG
     * @note If USB_UART_RX and USB_UART_TX 
     * are defined as HAL_PIN_NC, you will 
     * need to define them manually for log to work. 
     * See @b LOG_MAP_USB_UART macro definition for detailed explanation.
     */
    LOG_MAP_USB_UART( log_cfg );
    log_init( &logger, &log_cfg );
    log_info( &logger, " Application Init " );

    // Click initialization.
    adc21_cfg_setup( &adc21_cfg );
    ADC21_MAP_MIKROBUS( adc21_cfg, MIKROBUS_1 );
    if ( SPI_MASTER_ERROR == adc21_init( &adc21, &adc21_cfg ) )
    {
        log_error( &logger, " Communication init." );
        for ( ; ; );
    }
    
    log_info( &logger, " Application Task " );
}

void application_task ( void )
{
    static uint8_t ch_num = ADC21_CHANNEL_0;
    float ch_voltage;
    if ( ADC21_OK == adc21_read_voltage ( &adc21, ch_num, ADC21_AVCC_3V3, &ch_voltage ) )
    {
        log_printf ( &logger, " CH%u voltage: %.2f V\r\n", ( uint16_t ) ch_num, ch_voltage );
    }
    if ( ++ch_num > ADC21_CHANNEL_7 )
    {
        log_printf ( &logger, " ------------------------\r\n\n" );
        ch_num = ADC21_CHANNEL_0;
        Delay_ms ( 1000 );
    }
}

void main ( void )
{
    application_init( );

    for ( ; ; )
    {
        application_task( );
    }
}

// ------------------------------------------------------------------------ END

Additional Support

Resources