Connect multiple input sources to a common output thanks to the ADG728 and MK64FN1M0VDC12
Switch & stream: Analog multiplexer for seamless control
Published Oct 07, 2023
Click board™
Analog MUX 2 Click
Dev Board
Clicker 2 for Kinetis
Compiler
NECTO Studio
MCU
MK64FN1M0VDC12
Enhance your data acquisition and signal processing systems with our analog multiplexer solution, enabling precise selection and routing of analog inputs to optimize data analysis
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Hardware Overview
How does it work?
Analog MUX 2 Click is based on the ADG728, a low voltage, CMOS 8-channel analog matrix switch with a serially controlled 2-wire interface from Analog Devices. The ADG728 can operate equally well as a multiplexer, demultiplexer, or switch array, providing more flexibility. It also features a low on-resistance closely matched between switches and is flat over the full signal range. During the Power-Up of the ADG728, all switching channels will be in the OFF condition, and the internal shift register will contain all zeros. All channels exhibit a ‘break-before-make’ switching action, preventing momentary shorting when switching channels. Each bit of the 8-bit serial word corresponds to one device switch. Internal switching channels are independently controlled by an individual bit, providing an option to activate
any, all, or none of the switches. All of the input channels of the multiplexer can be easily connected to a nine-pole spring action block terminal without having to use any additional tools, such as screwdrivers, while the output pin from the multiplexer is routed to the AN pin on the mikroBUS™ socket. Analog MUX 2 Click communicates with MCU using the standard I2C 2-Wire interface with a frequency of up to 400kHz. It also has two address pins (A0 and A1) programmed by the user to determine the value of the last two LSBs of the slave address, selected by onboard SMD jumpers labeled as ADDR SEL to an appropriate position marked as 0 and 1, allowing selection of the slave address LSBs. Also, this Click board™ has a Reset pin routed to the RST pin on the mikroBUS™ socket, which
clears the input register and turns all switches to the OFF condition. A new 8-bit word is written to the input shift register when changing the switch conditions. The ADG728 compares the state of switches from the previous write cycle to minimize glitches on its outputs. This can be achieved if the switch is already in the ON condition and is required to stay ON. 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.
Features overview
Development board
Clicker 2 for Kinetis 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 ARM Cortex-M4F microcontroller, the MK64FN1M0VDC12 from NXP Semiconductors, two mikroBUS™ sockets for Click board™ connectivity, a USB connector, LED indicators, buttons, a JTAG programmer connector, and two 26-pin headers for interfacing with external electronics. Its compact design with clear and easily recognizable silkscreen markings allows you to build gadgets with unique functionalities and
features quickly. Each part of the Clicker 2 for Kinetis development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the Clicker 2 for Kinetis programming method, using a USB HID mikroBootloader or an external mikroProg connector for Kinetis programmer, the Clicker 2 board also includes a clean and regulated power supply module for the development kit. It provides two ways of board-powering; through the USB Micro-B cable, where onboard voltage regulators provide the appropriate voltage levels to each component on the board, or
using a Li-Polymer battery via an onboard battery connector. All communication methods that mikroBUS™ itself supports are on this board, including the well-established mikroBUS™ socket, reset button, and several user-configurable buttons and LED indicators. Clicker 2 for Kinetis 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.
Microcontroller Overview
MCU Card / MCU
Architecture
ARM Cortex-M4
MCU Memory (KB)
1024
Silicon Vendor
NXP
Pin count
121
RAM (Bytes)
262144
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Clicker 2 for Kinetis as your development board.
Track your results in real time
Application Output via Debug Mode
1. Once the code example is loaded, pressing the "DEBUG" button initiates the build process, programs it on the created setup, and enters Debug mode.
2. After the programming is completed, a header with buttons for various actions within the IDE becomes visible. Clicking the green "PLAY" button starts reading the results achieved with the Click board™. The achieved results are displayed in the Application Output tab.
Software Support
Library Description
This library contains API for Analog MUX 2 Click driver.
Key functions:
analogmux2_set_channel- Analog MUX 2 set channel functionanalogmux2_read_an_pin_value- Analog MUX 2 read AN pin value functionanalogmux2_read_an_pin_voltage- Analog MUX 2 read AN pin voltage level function
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 AnalogMux2 Click example
*
* # Description
* This application controls the multiplexing of a single input channel
* with an eight-channel matrix switch.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes I2C and ADC driver, set Vref, STM32F407ZG - 2.048 V, PIC18F97J94 3.3 V,
* set the default configuration and start to write log.
*
* ## Application Task
* This is an example that shows the use of a Analog MUX 2 click board.
* In this example, we switch from channel AN0 to channel AN7,
* read and display the analog value and voltage on the active channel.
* Results are being sent to the Usart Terminal where you can track their changes.
*
* @author Nenad Filipovic
*
*/
#include "board.h"
#include "log.h"
#include "analogmux2.h"
static analogmux2_t analogmux2;
static log_t logger;
void application_init ( void ) {
log_cfg_t log_cfg; /**< Logger config object. */
analogmux2_cfg_t analogmux2_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_printf( &logger, "\r\n" );
log_info( &logger, " Application Init " );
// Click initialization.
analogmux2_cfg_setup( &analogmux2_cfg );
ANALOGMUX2_MAP_MIKROBUS( analogmux2_cfg, MIKROBUS_1 );
// Vref STM32F407ZG
analogmux2_cfg.vref = 2.048;
err_t init_flag = analogmux2_init( &analogmux2, &analogmux2_cfg );
if ( init_flag == I2C_MASTER_ERROR ) {
log_error( &logger, " Application Init Error. " );
log_info( &logger, " Please, run program again... " );
for ( ; ; );
}
analogmux2_default_cfg ( &analogmux2 );
log_info( &logger, " Application Task " );
log_printf( &logger, "-------------------------\r\n" );
Delay_ms( 100 );
}
void application_task ( void ) {
for ( uint8_t ch_pos = ANALOGMUX2_SET_CHANNEL_0; ch_pos <= ANALOGMUX2_SET_CHANNEL_7; ch_pos++ ) {
analogmux2_set_channel( &analogmux2, ch_pos );
Delay_ms( 3000 );
uint16_t analogmux2_an_value = 0;
log_printf( &logger, " CHANNEL : AN%u \r\n", ( uint16_t ) analogmux2_get_channel( &analogmux2 ) );
log_printf( &logger, "- - - - - - - - - - - - - \r\n" );
if ( analogmux2_read_an_pin_value ( &analogmux2, &analogmux2_an_value ) != ADC_ERROR ) {
log_printf( &logger, " ADC Value : %u\r\n", analogmux2_an_value );
}
float analogmux2_an_voltage = 0;
if ( analogmux2_read_an_pin_voltage ( &analogmux2, &analogmux2_an_voltage ) != ADC_ERROR ) {
log_printf( &logger, " AN Voltage : %.3f V \r\n", analogmux2_an_voltage );
}
log_printf( &logger, "-------------------------\r\n" );
}
}
void main ( void ) {
application_init( );
for ( ; ; ) {
application_task( );
}
}
// ------------------------------------------------------------------------ END
