Intermediate
30 min
0

Enhance your designs with the next level of precision with MCP41HV51 and PIC18F25K80

Code your resistance

DIGI POT 6 Click with Curiosity HPC

Published Jan 23, 2024

Click board™

DIGI POT 6 Click

Development board

Curiosity HPC

Compiler

NECTO Studio

MCU

PIC18F25K80

Seamlessly bridge analog and digital realms using our digital potentiometer technology, harmonizing control and responsiveness for superior outcomes

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Hardware Overview

How does it work?

DIGI POT 6 Click is based on the MCP41HV51, 8-bit dual power rails digital potentiometer with SPI serial interface and volatile memory from Microchip. It has a wide operating voltage range, analog from 10 to 36V and digital from 2.7 to 5.5V, or is implemented as a dual-rail (±18V) for systems requiring wide signal swing or high power-supply voltages. It supports resistor configurations of 255 resistors and 256 steps and high terminal/wiper current, including the ability to sink/source up to 25mA on all terminal pins for driving larger loads. The resistor network of the MCP41HV51 has an 8-bit resolution where each resistor network allows

Zero-Scale to Full-Scale connections. All these features, combined with an extended temperature range, make the MCP41HV51 well-suited for a broad range of high-voltage and high-temperature applications, including those in the industrial, automotive, and audio markets. DIGI POT 6 click communicates with MCU using the SPI serial interface with a maximum frequency 10MHz and supports the two most common SPI modes, 0 and 3. This Click board™ also has three terminals labeled P0A, P0B, and P0W, with an internal architecture comprising various resistances and switches. The resistance between

terminals A and B, RAB, commonly called the “end-to-end” resistance, provides RAB resistance options up to 100 kΩ. In contrast, the wiper terminal, P0W, is digitally programmable to access any 2n tap points on the resistor string. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this 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.

DIGI POT 6 Click hardware overview image

Features overview

Development board

Curiosity HPC, standing for Curiosity High Pin Count (HPC) development board, supports 28- and 40-pin 8-bit PIC MCUs specially designed by Microchip for the needs of rapid development of embedded applications. This board has two unique PDIP sockets, surrounded by dual-row expansion headers, allowing connectivity to all pins on the populated PIC MCUs. It also contains a powerful onboard PICkit™ (PKOB), eliminating the need for an external programming/debugging tool, two mikroBUS™ sockets for Click board™ connectivity, a USB connector, a set of indicator LEDs, push button switches and a variable potentiometer. All

these features allow you to combine the strength of Microchip and Mikroe and create custom electronic solutions more efficiently than ever. Each part of the Curiosity HPC development board contains the components necessary for the most efficient operation of the same board. An integrated onboard PICkit™ (PKOB) allows low-voltage programming and in-circuit debugging for all supported devices. When used with the MPLAB® X Integrated Development Environment (IDE, version 3.0 or higher) or MPLAB® Xpress IDE, in-circuit debugging allows users to run, modify, and troubleshoot their custom software and hardware

quickly without the need for additional debugging tools. Besides, it includes a clean and regulated power supply block for the development board via the USB Micro-B connector, alongside all communication methods that mikroBUS™ itself supports. Curiosity HPC development board allows you to create a new application in just a few steps. Natively supported by Microchip software tools, it covers many aspects of prototyping thanks to many number of different Click boards™ (over a thousand boards), the number of which is growing daily.

Curiosity HPC double image

Microcontroller Overview

MCU Card / MCU

default

Architecture

PIC

MCU Memory (KB)

32

Silicon Vendor

Microchip

Pin count

28

RAM (Bytes)

3648

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
SPI Chip Select
RA3
CS
SPI Clock
RB1
SCK
SPI Data OUT
RB2
MISO
SPI Data IN
RB3
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

DIGI POT 6 Click Schematic schematic

Step by step

Project assembly

Curiosity HPC front no-mcu image hardware assembly

Start by selecting your development board and Click board™. Begin with the Curiosity HPC as your development board.

Curiosity HPC front no-mcu image hardware assembly
LTE Cat.1 2 Click front image hardware assembly
MCU DIP 28 hardware assembly
Prog-cut hardware assembly
LTE Cat.1 2 Click complete accessories setup image hardware assembly
Curiosity HPC Access 28pin-DIP - 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 DIP image step 7 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 DIGI POT 6 Click driver.

Key functions:

  • digipot6_read_data - This function reads data from the specified register address

  • digipot6_write_wiper_cmd - This function writes a wiper configuration command to the click module

  • digipot6_set_resistor - This function reads data from the specified register address

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 
 * \brief DIGIPOT6 Click example
 * 
 * # Description
 * This example showcases how to initialize, configure and use the DIGI POT 6 click module. The
 * click is a digital potentiometer. The potentiometer has a programmable wiper which controls 
 * the resistance between P0W-POA and POW-POB. An external power supply is required for this example.  
 *
 * The demo application is composed of two sections :
 * 
 * ## Application Init 
 * This function initializes and configures the logger and click modules. This function also sets
 * the click default configuration.
 * 
 * ## Application Task  
 * This function programs the wiper position and shows the current wiper position in the UART
 * console every second.
 * 
 * \author MikroE Team
 *
 */
// ------------------------------------------------------------------- INCLUDES

#include "board.h"
#include "log.h"
#include "digipot6.h"

// ------------------------------------------------------------------ VARIABLES

static digipot6_t digipot6;
static log_t logger;

// ------------------------------------------------------ APPLICATION FUNCTIONS

void application_init ( void )
{
    log_cfg_t log_cfg;
    digipot6_cfg_t cfg;

    /** 
     * 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.

    digipot6_cfg_setup( &cfg );
    DIGIPOT6_MAP_MIKROBUS( cfg, MIKROBUS_1 );
    digipot6_init( &digipot6, &cfg );
    Delay_100ms( );
    digipot6_default_cfg( &digipot6 );
    Delay_100ms( );
}

void application_task ( void )
{
    uint8_t wiper;
    uint16_t cnt;
    
    for ( cnt = 0; cnt <= 255; cnt += 15 )
    {
        digipot6_write_data( &digipot6, DIGIPOT6_VOLATILE_WIPER_0, cnt );
        Delay_ms( 10 );

        wiper = digipot6_read_data( &digipot6, DIGIPOT6_VOLATILE_WIPER_0 );

        log_printf( &logger, " * Wiper position: %u *\r\n", ( uint16_t ) wiper );
        Delay_ms( 1000 );
    }
}

void main ( void )
{
    application_init( );

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

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

Additional Support

Resources