Beginner
10 min

Unlock a new level of flexibility in resistance setting with TPL0501 and MK60DN512VLQ10

Control a voltage with digital signals

DIGI POT 2 Click with UNI-DS v8

Published Aug 21, 2023

Click board™

DIGI POT 2 Click

Dev Board

UNI-DS v8

Compiler

NECTO Studio

MCU

MK60DN512VLQ10

Enhance signal conditioning and gain control with our digital potentiometer, ensuring accurate and rapid adjustments in a digitally connected world

A

A

Hardware Overview

How does it work?

DIGI POT 2 Click is based on the TPL0501, a 256-taps, single-channel, digital potentiometer with an SPI interface from Texas Instruments. The TPL0501 can be used as a three-terminal potentiometer or a two-terminal rheostat. It has four screw terminals: A High terminal (H), a Low terminal (L), and two Wiper terminals (W), internally connected. The H and L terminals do not have polarity restrictions; H can be a higher voltage than L and vice-versa. The position of the wiper (W) terminal is controlled by the value in the 8-bit wiper resistance register. There are two functional

modes for the DIGI POT 2 Click. When all three terminals are used, the TPL0501 generates a voltage divider, where the voltage divider at wiper-to-H and wiper-to-L is proportional to the input voltage at H to L. It operates in rheostat mode as a variable resistor when only two terminals are used. Depending on the polarity, the variable resistance can be anywhere between the H and L terminals. In this case, the nominal resistance between H and L terminals is 10KΩ, and the TPL0501 has 256 tap positions of the wiper. DIGI POT 2 Click communicates with the host MCU using the

3-wire SPI serial interface as a write-only. The SCK timing frequency maximum is 25MHz. This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the PWR 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 2 Click top side image
DIGI POT 2 Click bottom side image

Features overview

Development board

UNI-DS v8 is a development board specially designed for the needs of rapid development of embedded applications. It supports a wide range of microcontrollers, such as different STM32, Kinetis, TIVA, CEC, MSP, PIC, dsPIC, PIC32, and AVR MCUs regardless of their number of pins, and a broad set of unique functions, such as the first-ever embedded debugger/programmer over WiFi. The development board is well organized and designed so that the end-user has all the necessary elements, such as switches, buttons, indicators, connectors, and others, in one place. Thanks to innovative manufacturing technology, UNI-DS v8 provides a fluid and immersive working experience, allowing access anywhere and under any

circumstances at any time. Each part of the UNI-DS v8 development board contains the components necessary for the most efficient operation of the same board. An advanced integrated CODEGRIP programmer/debugger module offers many valuable programming/debugging options, including support for JTAG, SWD, and SWO Trace (Single Wire Output)), and seamless integration with the Mikroe software environment. Besides, it also includes a clean and regulated power supply module for the development board. It can use a wide range of external power sources, including a battery, an external 12V power supply, and a power source via the USB Type-C (USB-C) connector. Communication options such as USB-UART, USB

HOST/DEVICE, CAN (on the MCU card, if supported), and Ethernet is also included. In addition, it also has the well-established mikroBUS™ standard, a standardized socket for the MCU card (SiBRAIN standard), and two display options for the TFT board line of products and character-based LCD. UNI-DS v8 is an integral part of the Mikroe ecosystem for rapid development. Natively supported by Mikroe software tools, it covers many aspects of prototyping and development thanks to a considerable number of different Click boards™ (over a thousand boards), the number of which is growing every day.

UNI-DS v8 horizontal image

Microcontroller Overview

MCU Card / MCU

default

Type

8th Generation

Architecture

ARM Cortex-M4

MCU Memory (KB)

512

Silicon Vendor

NXP

Pin count

144

RAM (Bytes)

131072

Used MCU Pins

mikroBUS™ mapper

NC
NC
AN
NC
NC
RST
SPI Chip Select
PE11
CS
SPI Clock
PB11
SCK
NC
NC
MISO
SPI Data IN
PB16
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 2 Click Schematic schematic

Step by step

Project assembly

Fusion for PIC v8 front image hardware assembly

Start by selecting your development board and Click board™. Begin with the UNI-DS v8 as your development board.

Fusion for PIC v8 front image hardware assembly
GNSS2 Click front image hardware assembly
SiBRAIN for PIC32MZ1024EFK144 front image hardware assembly
GNSS2 Click complete accessories setup image hardware assembly
v8 SiBRAIN Access MB 1 - upright/background hardware assembly
Necto image step 2 hardware assembly
Necto image step 3 hardware assembly
Necto image step 4 hardware assembly
NECTO Compiler Selection Step Image hardware assembly
NECTO Output Selection Step Image hardware assembly
Necto image step 6 hardware assembly
Necto image step 7 hardware assembly
Necto image step 8 hardware assembly
Necto image step 9 hardware assembly
Necto image step 10 hardware assembly
Necto PreFlash Image hardware assembly

Track your results in real time

Application Output via UART Mode

1. Once the code example is loaded, pressing the "FLASH" button initiates the build process, and programs it on the created setup.

2. After the programming is completed, click on the Tools icon in the upper-right panel, and select the UART Terminal.

3. After opening the UART Terminal tab, first check the baud rate setting in the Options menu (default is 115200). If this parameter is correct, activate the terminal by clicking the "CONNECT" button.

4. Now terminal status changes from Disconnected to Connected in green, and the data is displayed in the Received data field.

UART_Application_Output

Software Support

Library Description

This library contains API for DIGI POT 2 Click driver.

Key functions:

  • digipot2_set_wiper_positions - The function sets 8-bit wiper positions data

  • digipot2_convert_output - The function convert 10-bit ADC value to volatage reference

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 DigiPot2 Click example
 *
 * # Description
 * The demo application changes the resistance using DIGI POT 2 Click.
 *
 * The demo application is composed of two sections :
 *
 * ## Application Init
 * Initializes SPI and LOG modules.
 *
 * ## Application Task
 * This is an example which demonstrates the use of DIGI POT 2 Click board.
 * Increments the wiper position by 10 positions every 5 seconds.
 *
 * @author Stefan Ilic
 *
 */

#include "board.h"
#include "log.h"
#include "digipot2.h"

static digipot2_t digipot2;
static log_t logger;

uint8_t wiper_pos;

void application_init ( void ) {
    log_cfg_t log_cfg;  /**< Logger config object. */
    digipot2_cfg_t digipot2_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.

    digipot2_cfg_setup( &digipot2_cfg );
    DIGIPOT2_MAP_MIKROBUS( digipot2_cfg, MIKROBUS_1 );
    err_t init_flag  = digipot2_init( &digipot2, &digipot2_cfg );
    if ( SPI_MASTER_ERROR == init_flag ) {
        log_error( &logger, " Application Init Error. " );
        log_info( &logger, " Please, run program again... " );

        for ( ; ; );
    }

    log_printf( &logger, "----------------\r\n" );
    log_printf( &logger, " DIGI POT 2 Click\r\n" );
    log_printf( &logger, "----------------\r\n" );
}

void application_task ( void ) {
    for ( uint16_t n_cnt = 127; n_cnt < 255; n_cnt += 10 ) {
        wiper_pos = ( uint8_t ) n_cnt;
        digipot2_set_wiper_positions( &digipot2, wiper_pos );
        Delay_ms( 5000 );
    }
}

void main ( void ) {
    application_init( );

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

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

Additional Support

Resources

Love this project?

'Buy This Kit' button takes you directly to the shopping cart where you can easily add or remove products.