Achieve accurate and reliable data for RPM and speed measurements using LS7366R and STM32L073RZ
Counting with confidence: Your quadrature counter solution
Published Feb 26, 2024
Click board™
Counter Click
Dev Board
Nucleo-64 with STM32L073RZ MCU
Compiler
NECTO Studio
MCU
STM32L073RZ
Experience the precision of an advanced quadrature counter, designed to elevate your design with accurate motion measurements
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Hardware Overview
How does it work?
Counter Click is based on the LS7366R, a 32-bit quadrature counter with a serial interface from LSI Computer Systems. It is a CMOS counter with a direct interface for quadrature clocks from incremental encoders. It also interfaces with the index signals from incremental encoders to perform various marker functions. This counter can be configured to operate as a 1, 2, 3, or 4-byte counter. It can also be programmed to work in several counting modes such as Modulo-N, Non-recycle, Range-limit, or Free-running mode. This Click board™ features a 2x5 header (2.54mm pitch) with pins to interface the LS7366R inputs, VCC, and a few GNDs, basically the power supply
pins of the Click board™ itself. The VCC and GND pins can power the quadrature incremental encoder. This header also includes ENCA and ENCB, the input A and B pins of the LS7366R, to directly apply the quadrature clock outputs from incremental encoders on them, and Index (ENCI) pin, a programmable input driven directly by an incremental encoder's index output. The LS7366R uses a standard 4-wire SPI serial interface to communicate with the host MCU over the mikroBUS™ socket. The counter is enabled when EN input is in a high logic state; otherwise, it is disabled with a LOW logic level. In addition, this Click board™ features interrupt over INT pin that
can be configured to use LFLAG or DFLAG over the LF and DF solder jumpers with DFLAG set by default. This way, users can choose LFLAG, an open drain latched output, or DFLAG, an instantaneous push-pull output, thus using these outputs to flag Carry, Borrow, Compare, and Index occurrences. 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.
Features overview
Development board
Nucleo-64 with STM32L073RZ MCU offers a cost-effective and adaptable platform for developers to explore new ideas and prototype their designs. This board harnesses the versatility of the STM32 microcontroller, enabling users to select the optimal balance of performance and power consumption for their projects. It accommodates the STM32 microcontroller in the LQFP64 package and includes essential components such as a user LED, which doubles as an ARDUINO® signal, alongside user and reset push-buttons, and a 32.768kHz crystal oscillator for precise timing operations. Designed with expansion and flexibility in mind, the Nucleo-64 board features an ARDUINO® Uno V3 expansion connector and ST morpho extension pin
headers, granting complete access to the STM32's I/Os for comprehensive project integration. Power supply options are adaptable, supporting ST-LINK USB VBUS or external power sources, ensuring adaptability in various development environments. The board also has an on-board ST-LINK debugger/programmer with USB re-enumeration capability, simplifying the programming and debugging process. Moreover, the board is designed to simplify advanced development with its external SMPS for efficient Vcore logic supply, support for USB Device full speed or USB SNK/UFP full speed, and built-in cryptographic features, enhancing both the power efficiency and security of projects. Additional connectivity is
provided through dedicated connectors for external SMPS experimentation, a USB connector for the ST-LINK, and a MIPI® debug connector, expanding the possibilities for hardware interfacing and experimentation. Developers will find extensive support through comprehensive free software libraries and examples, courtesy of the STM32Cube MCU Package. This, combined with compatibility with a wide array of Integrated Development Environments (IDEs), including IAR Embedded Workbench®, MDK-ARM, and STM32CubeIDE, ensures a smooth and efficient development experience, allowing users to fully leverage the capabilities of the Nucleo-64 board in their projects.
Microcontroller Overview
MCU Card / MCU
Architecture
ARM Cortex-M0
MCU Memory (KB)
192
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
20480
You complete me!
Accessories
Click Shield for Nucleo-64 comes equipped with two proprietary mikroBUS™ sockets, allowing all the Click board™ devices to be interfaced with the STM32 Nucleo-64 board with no effort. This way, Mikroe allows its users to add any functionality from our ever-growing range of Click boards™, such as WiFi, GSM, GPS, Bluetooth, ZigBee, environmental sensors, LEDs, speech recognition, motor control, movement sensors, and many more. More than 1537 Click boards™, which can be stacked and integrated, are at your disposal. The STM32 Nucleo-64 boards are based on the microcontrollers in 64-pin packages, a 32-bit MCU with an ARM Cortex M4 processor operating at 84MHz, 512Kb Flash, and 96KB SRAM, divided into two regions where the top section represents the ST-Link/V2 debugger and programmer while the bottom section of the board is an actual development board. These boards are controlled and powered conveniently through a USB connection to program and efficiently debug the Nucleo-64 board out of the box, with an additional USB cable connected to the USB mini port on the board. Most of the STM32 microcontroller pins are brought to the IO pins on the left and right edge of the board, which are then connected to two existing mikroBUS™ sockets. This Click Shield also has several switches that perform functions such as selecting the logic levels of analog signals on mikroBUS™ sockets and selecting logic voltage levels of the mikroBUS™ sockets themselves. Besides, the user is offered the possibility of using any Click board™ with the help of existing bidirectional level-shifting voltage translators, regardless of whether the Click board™ operates at a 3.3V or 5V logic voltage level. Once you connect the STM32 Nucleo-64 board with our Click Shield for Nucleo-64, you can access hundreds of Click boards™, working with 3.3V or 5V logic voltage levels.
Used MCU Pins
mikroBUS™ mapper
Take a closer look
Click board™ Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Nucleo-64 with STM32L073RZ MCU as your development board.
Track your results in real time
Application Output
This Click board can be interfaced and monitored in two ways:
Application Output- Use the "Application Output" window in Debug mode for real-time data monitoring. Set it up properly by following this tutorial.
UART Terminal- Monitor data via the UART Terminal using a USB to UART converter. For detailed instructions, check out this tutorial.
Software Support
Library Description
This library contains API for Counter Click driver.
Key functions:
counter_read_cntr- This function reads CNTR, using click object.counter_read_str- This function reads STR, using click object.counter_read_otr- This function reads OTR, using click object.
Open Source
Code example
The complete application code and a ready-to-use project are available through the NECTO Studio Package Manager for direct installation in the NECTO Studio. The application code can also be found on the MIKROE GitHub account.
/*!
* \file
* \brief Counter Click example
*
* # Description
* This application measures the speed and the position of the DC motor shafts.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes driver and configures the click board.
*
* ## Application Task
* Reads data from the CNTR register and calculates the speed of the motor in Rad/s.
* All data is being displayed on the USB UART terminal where you can track their changes.
* The CNTR is a software configurable 8, 16, 24 or 32-bit up/down counter which
* counts the up/down pulses resulting from the quadrature clocks applied at the
* A and B inputs, or alternatively, in non-quadrature mode, pulses applied at the A input.
*
* ## NOTE
* An appropriate motor with optical encoder needs to be connected to the click board.
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "counter.h"
// ------------------------------------------------------------------ VARIABLES
static counter_t counter;
static log_t logger;
static int32_t count;
static int32_t count_old;
static float speed;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
counter_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.
counter_cfg_setup( &cfg );
COUNTER_MAP_MIKROBUS( cfg, MIKROBUS_1 );
counter_init( &counter, &cfg );
counter_default_cfg( &counter );
Delay_ms( 300 );
}
void application_task ( void )
{
count = counter_read_cntr( &counter );
log_printf( &logger, "Counter: %ld\r\n", count );
speed = ( float ) ( count - count_old ) / 3600.0;
speed *= 6.283185;
log_printf( &logger, "Speed: %.4f Rad/s\r\n", speed );
count_old = count;
log_printf( &logger, "-------------------------\r\n" );
Delay_ms( 1000 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
Additional Support
Resources
Category:Rotary encoder
