gistfile1.txt

Here is a step-by-step guide to implementing the IoT-Enabled Weather Station using VHDL on your DE2-70 board. The solution includes all necessary VHDL code, configurations, and explanations.


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Step 1: Install and Set Up Quartus II 9.1

1. Install Quartus II:

Ensure Quartus II 9.1 is installed.

Connect your DE2-70 board to your PC and verify drivers are installed.



2. Create a New Project:

Open Quartus II.

Navigate to File > New Project Wizard.

Specify the working directory and project name (e.g., IoT_WeatherStation).

For the device, select Cyclone II EP2C70F896C6.





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Step 2: Simulate Sensor Inputs Using Switches

1. Write VHDL Code to Simulate Sensors:

Use the DE2-70 switches to represent temperature, humidity, and pressure sensors.

Example VHDL Code:

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity SensorSimulator is
    Port (
        SW : in STD_LOGIC_VECTOR (2 downto 0); -- Switch inputs
        TEMP : out STD_LOGIC_VECTOR (7 downto 0); -- Temperature
        HUMIDITY : out STD_LOGIC_VECTOR (7 downto 0); -- Humidity
        PRESSURE : out STD_LOGIC_VECTOR (7 downto 0) -- Pressure
    );
end SensorSimulator;

architecture Behavioral of SensorSimulator is
begin
    TEMP <= "00011001" when SW(0) = '1' else "00000000";      -- 25°C
    HUMIDITY <= "00110010" when SW(1) = '1' else "00000000";  -- 50%
    PRESSURE <= "01100101" when SW(2) = '1' else "00000000";  -- 101 kPa
end Behavioral;



2. Compile the Code:

Save the file as SensorSimulator.vhd.

Add it to your Quartus project and compile.





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Step 3: Display Sensor Values on the LCD

1. Understand the LCD Module on DE2-70:

The LCD has specific control signals (e.g., RS, E, DATA[7:0]).

Refer to the DE2-70 manual for pin mappings.



2. Write VHDL Code for LCD Controller:

Implement a driver to send data to the LCD.

Example Code:

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity LCDController is
    Port (
        CLK : in STD_LOGIC; -- Clock
        TEMP : in STD_LOGIC_VECTOR (7 downto 0);
        HUMIDITY : in STD_LOGIC_VECTOR (7 downto 0);
        PRESSURE : in STD_LOGIC_VECTOR (7 downto 0);
        LCD_DATA : out STD_LOGIC_VECTOR (7 downto 0);
        LCD_RS : out STD_LOGIC;
        LCD_E : out STD_LOGIC
    );
end LCDController;

architecture Behavioral of LCDController is
    signal message : STD_LOGIC_VECTOR (23 downto 0);
    signal count : integer range 0 to 24 := 0;
begin
    process(CLK)
    begin
        if rising_edge(CLK) then
            message <= TEMP & HUMIDITY & PRESSURE; -- Combine values
            LCD_DATA <= message(count * 8 + 7 downto count * 8); -- Send each byte
            count <= count + 1;
            if count = 3 then
                count <= 0;
            end if;
            LCD_RS <= '1'; -- Data mode
            LCD_E <= '1';
        end if;
    end process;
end Behavioral;



3. Compile and Test:

Save this file as LCDController.vhd.

Add it to your project and ensure compilation succeeds.





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Step 4: Implement UART Communication

1. Write UART Transmitter Module:

Transmit sensor data via UART.

Example Code:

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity UARTTransmitter is
    Port (
        CLK : in STD_LOGIC;
        DATA : in STD_LOGIC_VECTOR (7 downto 0);
        TX : out STD_LOGIC
    );
end UARTTransmitter;

architecture Behavioral of UARTTransmitter is
    signal baud_counter : integer := 0;
    signal tx_data : STD_LOGIC_VECTOR (9 downto 0);
    signal tx_index : integer range 0 to 9 := 0;
    signal sending : STD_LOGIC := '0';
begin
    process(CLK)
    begin
        if rising_edge(CLK) then
            if sending = '0' then
                tx_data <= '0' & DATA & '1'; -- Start + Data + Stop bits
                sending <= '1';
                tx_index <= 0;
            elsif baud_counter = 5208 then -- Assuming 50 MHz clock for 9600 baud rate
                TX <= tx_data(tx_index);
                tx_index <= tx_index + 1;
                baud_counter <= 0;
                if tx_index = 9 then
                    sending <= '0';
                end if;
            else
                baud_counter <= baud_counter + 1;
            end if;
        end if;
    end process;
end Behavioral;



2. Integrate UART with Sensor Data:

Combine the UARTTransmitter with the SensorSimulator.



3. Test UART:

Use a USB-UART adapter and a serial terminal to verify transmitted data.





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Step 5: Combine All Modules

1. Write Top-Level Module:

Integrate SensorSimulator, LCDController, and UARTTransmitter.

Example:

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;

entity WeatherStation is
    Port (
        SW : in STD_LOGIC_VECTOR (2 downto 0);
        CLK : in STD_LOGIC;
        LCD_DATA : out STD_LOGIC_VECTOR (7 downto 0);
        LCD_RS : out STD_LOGIC;
        LCD_E : out STD_LOGIC;
        TX : out STD_LOGIC
    );
end WeatherStation;

architecture Structural of WeatherStation is
    signal TEMP, HUMIDITY, PRESSURE : STD_LOGIC_VECTOR (7 downto 0);
begin
    SensorSim : entity work.SensorSimulator
        Port map (SW => SW, TEMP => TEMP, HUMIDITY => HUMIDITY, PRESSURE => PRESSURE);

    LCDCtrl : entity work.LCDController
        Port map (CLK => CLK, TEMP => TEMP, HUMIDITY => HUMIDITY, PRESSURE => PRESSURE,
                  LCD_DATA => LCD_DATA, LCD_RS => LCD_RS, LCD_E => LCD_E);

    UARTTx : entity work.UARTTransmitter
        Port map (CLK => CLK, DATA => TEMP, TX => TX);
end Structural;



2. Compile and Generate Programming File:

Click Processing > Start Compilation.

Generate a .sof file.





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Step 6: Program the Board

1. Assign Pins:

Open Assignments > Pin Planner.

Map:

SW[2:0] to the switches.

LCD_DATA, LCD_RS, LCD_E to LCD pins.

TX to UART TX pin.




2. Program the Board:

Open Tools > Programmer.

Load the .sof file and program your DE2-70 board.





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Step 7: Verify

1. Flip switches and observe:

Correct sensor values on the LCD.

Correct UART data on the serial terminal.



2. Debug any issues by revisiting individual modules.




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This guide ensures everything is covered. Let me know if you encounter any issues!