Achieve the most reliable magnet angle measurements with AEAT-8800-Q24 and STM32F373VC
Detecting magnet rotation with ease
Published Sep 15, 2023
Click board™
Angle 4 Click
Dev Board
UNI Clicker
Compiler
NECTO Studio
MCU
STM32F373VC
Dive into the limitless possibilities unlocked by our magnet rotation sensing solution, empowering engineers and innovators to create smarter, more responsive systems
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Hardware Overview
How does it work?
Angle 4 Click is based on the AEAT-8800-Q24, an integrated 10 to 16-bit programmable angular magnetic encoder from Broadcom. This sensor relies on integrated Hall elements and complex analog front end and digital signal processing, in order to provide absolute angular position over the industry standard SPI interface. The user has the ability to programmatically set the zero position, direction, hysteresis, and the resolution. This allows the Click board™ to be tailored according to needs for a range of different applications. The possibility to sense the rotational angle of a diametrically magnetized object parallel with the Click board™ surface, gives an opportunity to develop both contactless rotational and positional measurement applications, as well as the human-machine interfaces (HMI), such as the rotary encoders, digital potentiometers, and similar. The calibration is simple, and the AEAT-8800-Q24 datasheet provides a detailed explanation
how to calibrate the device by using a diametrically magnetized object (i.e. a magnetic disc), with its axis aligned to the center of the sensor. For the best results, the magnet properties should be according to specifications in the datasheet. Once calibrated, it can be permanently used, with no additional recalibrations. The AEAT-8800-Q24 uses the non-volatile one-time programming memory during the operation. It contains registers with the calibration values, zero offsets, resolution and so on. All the OTP locations have their shadow locations, which allow writing, but only when the unlock command is issued (writing 0xAB to the location 0x10). However, the values will be lost after the power cycle and will be rewritten with the values contained in the OTP memory. The library provided with Angle 4 click offers several simple and useful functions, among which is the angle4_calibration function, which will automatically program the direction and the
resolution parameters to the OTP memory, passed as argumetns to this function. However, the OTP memory will not be permanently written, unless appropriate programming voltage is applied to the VDDP pin. Since the OTP memory can be programmed only once, a thorough understanding of the OTP programming process is required. More information about the OTP programming process can be found in the AEAT-8800-Q24 datasheet. 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
UNI Clicker is a compact development board designed as a complete solution that brings the flexibility of add-on Click boards™ to your favorite microcontroller, making it a perfect starter kit for implementing your ideas. It supports a wide range of microcontrollers, such as different ARM, PIC32, dsPIC, PIC, and AVR from various vendors like Microchip, ST, NXP, and TI (regardless of their number of pins), four mikroBUS™ sockets for Click board™ connectivity, a USB connector, LED indicators, buttons, a debugger/programmer connector, and two 26-pin headers for interfacing with external electronics. Thanks to innovative manufacturing technology, it allows you to build
gadgets with unique functionalities and features quickly. Each part of the UNI Clicker development kit contains the components necessary for the most efficient operation of the same board. In addition to the possibility of choosing the UNI Clicker programming method, using a third-party programmer or CODEGRIP/mikroProg connected to onboard JTAG/SWD header, the UNI Clicker board also includes a clean and regulated power supply module for the development kit. It provides two ways of board-powering; through the USB Type-C (USB-C) connector, where onboard voltage regulators provide the appropriate voltage levels to each component on the board, or using a Li-Po/Li
Ion battery via an onboard battery connector. All communication methods that mikroBUS™ itself supports are on this board (plus USB HOST/DEVICE), including the well-established mikroBUS™ socket, a standardized socket for the MCU card (SiBRAIN standard), and several user-configurable buttons and LED indicators. UNI 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.
Microcontroller Overview
MCU Card / MCU
Type
8th Generation
Architecture
ARM Cortex-M4
MCU Memory (KB)
256
Silicon Vendor
STMicroelectronics
Pin count
100
RAM (Bytes)
49152
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 UNI Clicker as your development board.
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.
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™.
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.
Software Support
Library Description
This library contains API for Angle 4 Click driver.
Key functions:
angle4_start_mesuremenet- This function is used to start measurement modeangle4_get_new_angle- This function is used to retrieve Angle value depending on the given resolutionangle4_read_byte- This function is used to read single byte of Data on the desired 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 Angle4 Click example
*
* # Description
* This application enables use of angular magnetic rotary sensor, which can be used as a rotary encoder.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Driver intialization, standard configurations and start measurement
*
* ## Application Task
* Reads Angle in degreeses and logs data to USBUART every 200 ms.
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "angle4.h"
// ------------------------------------------------------------------ VARIABLES
static angle4_t angle4;
static log_t logger;
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
angle4_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.
angle4_cfg_setup( &cfg );
ANGLE4_MAP_MIKROBUS( cfg, MIKROBUS_1 );
angle4_init( &angle4, &cfg );
angle4_default_cfg( &angle4, ANGLE4_CCFG2_DIR_COUNTER_CLOCKWISE_ROTATION,\
ANGLE4_CCFG2_ABS_RESOLUTION_14bit );
log_printf( &logger, " --- Start measurement \r\n");
angle4_start_mesuremenet( &angle4 );
}
void application_task ( void )
{
// Task implementation.
uint16_t angle_value;
angle4_get_new_angle( &angle4, &angle_value );
log_printf( &logger, " Angle : %d deg\r\n", angle_value );
Delay_ms( 200 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
