This project was done for PC/CP220 class at WLU, Fall 2016
Braille Number Encoder Circuit is designed to help blind or visually damaged people. The system converts binary representation of number from 0 up to 9, to a visual pattern as shown in the figure below.
Binary number to Braille Number conversion:
Using DIP switch, Braille Number Encoder Circuit will have four inputs, i_0 to i_3, in which they are used to provide the binary number representation from 0 to 9.
According to Decimal-Binary conversion table:
Using LEDs outputs, Braille Number Encoder Circuit will have six outputs, p0 to p5, like Figure 2 which is oriented in the patterns as seen in figure1. LEDs must light(ON) to give every number a distinct pattern as shown in the figure.
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The system is using visual representation by using LEDs with the assumption that a physical dot output should be raised in replace of each ON LED.
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Although we only need four outputs to represent the pattern of a number from 0 to 9; We are using six outputs, In case the system may developed to include the whole Braille alphanumeric system which needs all the six outputs.
The project has six outputs from P_0 to P_5, but P_2 and P_3 are not in use. Therefore, we only have four logic equations to implement:
where i_3 is the most significant bit of the input, and i_0 is the least significant bit of the input. We test the logic in file Logic_Testing.pdf
Altera Quartus II is used to draw our circuit, and is shown in the following figure.
For four bits combination we have 16 possibilities. Since we are only interested in the decimals from 0 to 9, we are going to ignore the possibilities which are 1010, 1011, 1100, 1101, 1110, and 1111. Based on the simulation followed below, we can prove that all of results are true.
• CPLD Board for prototyping the design
• DIP switch for the inputs
• 1kΩ Resistor array for the DIP switch
• 6 LEDs for the outputs
• 6 of 510Ω Resistors for the LEDs