| Line 136... |
Line 136... |
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-- Synchronization FF chain for asynchronous reset input
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-- Synchronization FF chain for asynchronous reset input
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signal reset_sync : std_logic_vector(3 downto 0);
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signal reset_sync : std_logic_vector(3 downto 0);
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-- Reset pushbutton debouncing logic
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-- Reset pushbutton debouncing logic
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subtype t_debouncer is integer range 0 to CLOCK_FREQ*4;
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subtype t_debouncer is natural range 0 to CLOCK_FREQ*4;
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constant DEBOUNCING_DELAY : t_debouncer := 1500;
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constant DEBOUNCING_DELAY : t_debouncer := 1500;
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signal debouncing_counter : t_debouncer := (CLOCK_FREQ/1000) * DEBOUNCING_DELAY;
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signal debouncing_counter : t_debouncer := (CLOCK_FREQ/1000) * DEBOUNCING_DELAY;
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-- Quad 7-segment display (non multiplexed) & LEDS
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-- Quad 7-segment display (non multiplexed) & LEDS
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signal display_data : std_logic_vector(15 downto 0);
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signal display_data : std_logic_vector(15 downto 0);
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| Line 256... |
Line 256... |
clk => clk,
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clk => clk,
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reset => reset
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reset => reset
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);
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);
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--##############################################################################
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--##############################################################################
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-- GPIO and LEDs
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-- GPIO and LEDs
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--##############################################################################
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--##############################################################################
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---- LEDS -- We'll use the LEDs to display debug info --------------------------
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---- LEDS -- We'll use the LEDs to display debug info --------------------------
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-- HEX display is mostly unused
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-- HEX display is mostly unused
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reg_display <= p0_out(31 downto 16);
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reg_display <= p0_out(31 downto 16);
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-- Show the SD interface signals on the green leds for debug
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-- Show the SD interface signals on the green leds for debug
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reg_gleds <= p1_in(0) & "0000" & p0_out(2 downto 0);
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reg_gleds <= p1_in(0) & "0000" & p0_out(2 downto 0);
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-- Red leds (light with '1') -- some CPU control signals
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-- Red leds (light with '1') -- some CPU control signals
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red_leds(0) <= debug_info.cache_enabled;
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red_leds(0) <= debug_info.cache_enabled;
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| Line 277... |
Line 279... |
red_leds(3) <= '0';
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red_leds(3) <= '0';
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red_leds(4) <= '0';
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red_leds(4) <= '0';
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red_leds(5) <= '0';
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red_leds(5) <= '0';
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red_leds(6) <= '0';
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red_leds(6) <= '0';
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red_leds(7) <= '0';
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red_leds(7) <= '0';
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red_leds(8) <= '0';
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red_leds(8) <= reset;
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red_leds(9) <= clk_1hz;
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red_leds(9) <= clk_1hz;
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--##############################################################################
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--##############################################################################
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-- terasIC Cyclone II STARTER KIT BOARD -- interface to on-board devices
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-- terasIC Cyclone II STARTER KIT BOARD -- interface to on-board devices
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| Line 362... |
Line 364... |
end if;
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end if;
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end if;
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end if;
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end if;
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end if;
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end process reset_debouncing;
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end process reset_debouncing;
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--
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-- Reset will be active and glitch free for some serious time (1.5 s).
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reset <= '1' when debouncing_counter /= 0 or pll_locked='0' else '0';
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reset <= '1' when debouncing_counter /= 0 or pll_locked='0' else '0';
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-- Generate a 1-Hz 'clock' to flash a LED for visual reference.
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-- Generate a 1-Hz 'clock' to flash a LED for visual reference.
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process(clk)
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process(clk)
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begin
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begin
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