Hardware Reference
In-Depth Information
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begin
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if rst_lcd='1' then
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pr_state <= FunctionSet1;
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elsif rising_edge(E) then
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pr_state <= nx_state;
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end if;
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end process;
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--FSM combinational logic:
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process (all)
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begin
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case pr_state is
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--Initialization:
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when FunctionSet1 =>
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RS <= '0';
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DB <= "00111000";
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nx_state <= FunctionSet2;
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when FunctionSet2 =>
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RS <= '0';
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DB <= "00111000";
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nx_state <= FunctionSet3;
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when FunctionSet3 =>
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RS <= '0';
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DB <= "00111000";
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nx_state <= FunctionSet4;
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when FunctionSet4 =>
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RS <= '0';
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DB <= "00111000";
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nx_state <= ClearDisplay;
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when ClearDisplay =>
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RS <= '0';
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DB <= "00000001";
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nx_state <= DisplayControl;
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when DisplayControl =>
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RS <= '0';
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DB <= "00001100";
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nx_state <= EntryMode;
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when EntryMode =>
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RS <= '0';
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DB <= "00000110";
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nx_state <= WriteHourT;
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--Write data:
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when WriteHourT =>
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RS <= '1';
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DB <= bcd_to_lcd(hourT);
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nx_state <= WriteHourU;
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when WriteHourU =>
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RS <= '1';
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DB <= bcd_to_lcd(hourU);
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nx_state <= WriteColon1;
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when WriteColon1 =>
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RS <= '1';
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DB <= "00111010";
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nx_state <= WriteMinT;
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when WriteMinT =>
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RS <= '1';
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DB <= bcd_to_lcd(minT);
