Elevate your messaging game with SLO2016 and STM32F091RC
4-digit brilliance at your fingertips!
Published Feb 26, 2024
Click board™
4Dot-Matrix R Click
Dev Board
Nucleo-64 with STM32F091RC MCU
Compiler
NECTO Studio
MCU
STM32F091RC
Step into the future with our cutting-edge display solution, showcasing information digit by digit through our four-digit red dot matrix display module
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Hardware Overview
How does it work?
4Dot-Matrix R Click is based on the SLO2016, 4-Digit 5x7 dot matrix alphanumeric Intelligent Display® device with the integrated memory, ASCII decoder, and driver sections, from ams OSRAM. This allows a high autonomy of the module, without any type of display refresh or multiplexing within the application. The character selection is easy, and it is done via the parallel interface, asynchronously. The logic states on seven data pins (D0 to D6) are translated into seven characters selection bits, with two additional pins, used to select the display position of the character (A0 to A1). There are four possible position selections in total, starting with the position 0 at the rightmost position. The display module contains internal memory with 128 ASCII characters. It contains some special characters too, including letters for English, German, Italian, Swedish, Danish, and Norwegian languages, as well as some other special characters and symbols. The internal character memory cannot be altered, it is read-only. A character which is once selected and displayed at the specific position will remain lit, as long as there is a power supply, or unless it
is blanked out or changed. The module itself operates at 5V. To provide the top performance, each module is tested and subjected to the burn-in procedure. A special care is taken by the manufacturer for each pixel to be displayed equally bright and clear. The display is robust and can sustain a significant electrostatic discharge (ESD). However, a care should be taken when working with the device, since not all the components are ESD resistant. The parallel data interface is coupled with the MCP23017, a 16-bit I/O expander with I2C interface, from Microchip. This device allows using only two pins (I2S Clock and I2S Data) to control all seven data bits and two more position bits. The expander pins on the B port are used as the character selection pins, while two pins from the A port of the expander are used as the positional data pins. The rest of the control lines, such as the #BL (display blanking), #WR (write enable), and #CLR (memory clear) are routed to the mikroBUS™ PWM, CS, and RST pins, respectively. Applying a PWM signal to the #BL pin of the display module will allow dimming of the display, depending on the duty cycle of
the input signal. To completely dim the display, the BL pin needs to be pulled to a LOW logic level. It is also possible to dim the display by displaying the blank characters. The recommended frequency when using the PWM dimming function is 2.5 kHz and above. The I2C address of the port expander can be selected by switching three onboard SMD jumpers, labeled as ADDR SEL. These jumpers define the least significant bits of the I2C address, so more than one device can be used on the same I2C bus. Besides the I2C address, it is possible to select the communication voltage level, by switching the SMD jumper labeled as the LOGIC SEL. For this purpose, four-level shifting ICs are employed, of which three are labeled as SN74LVC1T45, single-bit dual-supply bus transceivers, and one for the I2C signal, labeled as the PCA9306, a dual bidirectional I2C bus voltage translator, both from Texas Instruments. These ICs allow simple and reliable bit level shifting functions, by utilizing two different reference voltages to which the logic levels are translated. This allows the Click board™ to be interfaced with both 3.3V and 5V MCUs.
Features overview
Development board
Nucleo-64 with STM32F091RC 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)
256
Silicon Vendor
STMicroelectronics
Pin count
64
RAM (Bytes)
32768
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
Schematic
Step by step
Project assembly
Start by selecting your development board and Click board™. Begin with the Nucleo-64 with STM32F091RC MCU 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 4Dot-Matrix R Click driver.
Key functions:
c4dot_write_char- 4DotMatrix Char Write.c4dot_write_char0- 4DotMatrix Char 0 Write.c4dot_write_text- 4DotMatrix Text Write.
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 c4dotmatrixr Click example
*
* # Description
* This example demonstrates the use of 4Dot-Matrix R click board.
*
* The demo application is composed of two sections :
*
* ## Application Init
* Initializes the driver and performs the click default configuration.
*
* ## Application Task
* Displays a desired text message and then numbers from -20 to 20 on the click board.
* Each step will be logged on the USB UART where you can track the program flow.
*
* \author MikroE Team
*
*/
// ------------------------------------------------------------------- INCLUDES
#include "board.h"
#include "log.h"
#include "c4dotmatrixr.h"
// ------------------------------------------------------------------ VARIABLES
static c4dotmatrixr_t c4dotmatrixr;
static log_t logger;
static uint8_t text[23] = { ' ',' ',' ','M', 'i', 'k', 'r', 'o', 'E','l','e',
'k','t','r','o','n','i','k','a',' ',' ',' ',' '};
// ------------------------------------------------------ APPLICATION FUNCTIONS
void application_init ( void )
{
log_cfg_t log_cfg;
c4dotmatrixr_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.
c4dotmatrixr_cfg_setup( &cfg );
C4DOTMATRIXR_MAP_MIKROBUS( cfg, MIKROBUS_1 );
c4dotmatrixr_init( &c4dotmatrixr, &cfg );
c4dotmatrixr_default_cfg ( &c4dotmatrixr );
log_info( &logger, "---- Application Task ----" );
}
void application_task ( void )
{
int8_t i;
log_printf( &logger, "------------------------------------\r\n" );
log_printf( &logger, "Displaying \"Mikroelektronika\" on the click board...\r\n" );
for ( i = 0; i < 20; i++ )
{
c4dot_write_text( &c4dotmatrixr, text + i );
Delay_ms( 150 );
}
// Clear and delay.
c4dot_clear_display( &c4dotmatrixr );
Delay_ms( 500 );
log_printf( &logger, "Displaying all integer numbers from -20 to 20 on the click board...\r\n" );
// Write some numbers on the display.
for ( i = -20; i <= 20; i++ )
{
c4dot_write_int_dec( &c4dotmatrixr, i );
Delay_ms( 150 );
}
// Clear and delay.
c4dot_clear_display( &c4dotmatrixr );
Delay_ms( 500 );
}
void main ( void )
{
application_init( );
for ( ; ; )
{
application_task( );
}
}
// ------------------------------------------------------------------------ END
