The Custom-built matrix display for Primary Kids’ Character Visualisation” is an accessible innovation that revolutionises primary education.8×8 Programmable Matrix Display is a seamless and dynamic platform for young learners to discover and understand characters in a visually alphabets number with its user-friendly programmable feature. With cutting-edge technology in the classroom, it is an economical option that improves learning without taxing resources because of its low-cost design. This method fosters a deeper comprehension of language and characters while also igniting curiosity by skilfully fusing current technologies and education. Matrix display, which embraces the possibilities of technology, paves the way for a more engaging and effective learning experience by giving primary school students the tools they need to begin off on an interesting path of character discovery and literacy growth.
Circuit and Working
The matrix display is constructed as rows and columns interfaced with the Arduino Uno. The columns are connected to the LEDs’ cathodes, which means that a column needs to be set to a low state to turn on LED, while the rows are connected to the anodes of the LEDs, to make the row set HIGH for an individual LED to turn on. If both the row and the column are either HIGH or LOW simultaneously, no voltage will flow through the LED, resulting in it remains OFF. To control a specific LED, the column corresponding to that LED must set to LOW, while its row should be HIGH.
To control multiple LEDs within a row on the matrix display, the row is set to a HIGH state initially. Then, the column associated with the LEDs to be controlled is set to a LOW state. Subsequently, the individual columns can be set to either a HIGH or LOW state based on the desired LED states. Setting a column to a HIGH state will turn off the corresponding LED in that column and row, while setting it to a LOW state will turn on the LED. By selectively setting the columns to the HIGH or LOW state, specific LEDs within the row can be turned ON or OFF accordingly, allowing for the control of multiple LEDs simultaneously.
- While working in coding, pin should be assigned as the rows (r1-r8) and columns (c1-c8) and in void setup give pin mode for all the rows and columns as OUTPUT. Then define following function
- onr: Turns on a specific row by setting the corresponding row pin to a HIGH state.
- onc: Turns on a specific column by setting the corresponding column pin to a LOW state.
- offr: Turns off a specific row by setting the corresponding row pin to a LOW state.
- offc: Turns off a specific column by setting the corresponding column pin to a HIGH state.
- off_all: Turns off all rows and columns of the LED matrix by calling the offr and offc functions for each row and column pin.
The delay(t) is introduced to make a delay between each step to control the display timing.
Construction and Testing
The matrix display interfacing with Arduino UNO is constructed using 64 SMD 1206 LED and 1K ohm resistors as shown in figure 1, to avoid the intersection of circuit lines 0 ohm resistors are used.
First stage of developing the SMD PCB 8×8 matrix display. Initially, the PCB layout is drawn using eda tool software and exported in PNG file format as shown in figure 2.2 which is imported to the EzCAD for laser etching on the FR4 board. With that the bare board for matrix display is designed using laser etching machine, shown in figure 3.
The second stage is assembling the components, after cleaning the etched board, then a generous amount of solder paste applied on the solder pad and by using a pick and place machine place the components are mounted on the corresponding positions.
The last stage of the fabrication of the PCB board is soldering, here we used Reflow oven to solder the components using the hot air blowing method. The 5 chambers of the reflow oven’s temperature and fan are set in increasing order to have a proper soldering finish.
Male-to-male connectors is hand-soldered for interfacing with the Arduino UNO. After completing the soldering, check the circuit connection whether there is any short or open circuit was created in the process. Connect the PCB board with Arduino and upload the program to visualise the output.
Concluding
The table below shows the fundamental components required for the display Arduino interface. This led matrix can be used to form multiple patterns using an Arduino program with high and low concept. Figure 6 shows the finished product and displayed sample output as EFY light illusion in 8×8 LED matrix display. This circuit can be power up to a 5V DC supply.
| PARTS LIST |
| SMD LEDs (1206): 64 |
| SMD Resistors (1206): 8(1K ohm), 56(0 ohm) |
| Single male-male pin connector |
| FR4 board (10×10) cm |
Changing the way elementary education is approached, the “Teaching Aid 8×8 Programmable Matrix Display for Primary Kids’ Character Visualisation” is a cutting-edge and captivating tool. This educational tool provides a dynamic and engaging platform for kids to discover and interpret characters in a visually appealing way thanks to its adjustable matrix display. This method develops a deeper comprehension of language and characters while also igniting curiosity by seamlessly merging technology and education. This teaching tool sets the way for a more immersive and effective learning experience as we continue to embrace the potential of contemporary technology, enabling elementary students on their journey of character discovery and literacy development.
