Honored Contributorhi,
how can I write a program for a timer which Measures a pulse width that represents of range.i'm using un ultrasonic sensor, The distance can be calculated using the scale factor of 147uS per inch. thanks in advance
Honored Contributoryou need a counter, and the size of the count to trigger a "20 seconds elapsed" signal will depend on your clock speed.
Honored ContributorHi
I want to design traffic light controller using AHDL so I writ the code for traffic controller and for the timers and all is successful individual but when I design the circuit for all and connected to gather I have three error but I do not know how to fix it so please can some one help me and tell me what must I do. Thank you this is the error [1] Error: Port "100_cnt" does not exist in macrofunction "inst20". [2] Error: Quartus II Analysis & Synthesis was unsuccessful. 1 error, 11 warnings. [3] Error: Quartus II Full Compilation was unsuccessful. 3 errors, 11 warnings. What dose mean about macrofunction.Honored ContributorYou have a component called "inst20" in your design, and when you instantiate it in your code you are trying to connect a signal to one of its ports that you called "100_cnt" but this port doesn't exist.
Do you have any reason why you are using the deprecated AHDL and not VHDL?Honored ContributorOk I wrote this code for timer 2 second in Ahdl so please how can I convert it to VHDL
SUBDESIGN 2_sec_cnt ( clk ,enl: INPUT; 2_second : OUTPUT; ) VARIABLE count[25..0] : DFF; BEGIN count[].clk = clk; IF (enl)Then IF ((count[].q == 48000000)) THEN count[].d = 0; 2_second = VCC; ELSE count[].d = count[].q + 1; 2_second = GND; END IF; Else 2_second = GND; END IF; END;Honored ContributorYes I understood what is my circuit it is about traffic light controller so this timer for the yellow light in traffic and I wrote the Vhdl code for the Traffic controller but still I have the timer and this AHDL 2 second timer for traffic also so how can I convert it to VHDL.
Honored ContributorThe code logic and structure by itself is the same so, you can almost just take each line and change it to it's VHDL equivalent. Why don't you try it and show us what you wrote, if you have more questions? It is really basic VHDL.
The only big difference in VHDL is that you will have to put everything in a process, and specify that you want it executed on the rising edge of clk.Honored ContributorOk this is what I wrote in VHDL and when I run the code (in quartus II) I got success put when I go to the RTL viewer to draw the circuit I gut only the pin for input and output but when I do the same for AHDL code I have very big and different circuit.
library IEEE; use IEEE.STD_LOGIC_1164.all; entity two is Port ( clk : in std_logic; enl : in std_logic; second : out std_logic ); end two; architecture Timer of two is constant count : natural := 48000000; -- I used 24MHz clock begin process (clk, enl) variable count : natural range 0 to count; begin if (enl ='1') then if (count = 48000000) then count := 0 ; second <= '1'; else count := count+1; second <= '0'; end if ; second <= '0'; end if ; end process; end Timer;Honored ContributorFirst I suggest that you rename your constant "count" to "count_max" for example, to avoid confusion between the constant and the variable.
Then in VHDL you need to explicitely say that you want something done on each rising edge of the clock:process (clk, enl)
variable count : natural range 0 to count;
begin
if rising_edge(clk) then
if (enl ='1') then
if (count = 48000000) then
count := 0 ;
second <= '1';
else
count := count+1;
second <= '0';
end if ;
second <= '0';
end if ;
end if;
end process;hie i am a newbie ..
i managed to create a program that read input from the PIR sensor from the gpio and when sensor sense movement it will turn on and LED on the DE2 board. how can i write the timer that stays on for 5 to 10 minutes. here i attcehed my code... library IEEE; use ieee.std_logic_1164.all; use IEEE.numeric_std.all; entity ltestinggpiowithdelay is port( GPIO_0 : in std_logic_vector(2 downto 0); q : out std_logic_vector(2 downto 0)); end ltestinggpiowithdelay ; architecture bufferwithGpio_arc of ltestinggpiowithdelay is begin process(GPIO_0) begin if (GPIO_0(0)='1') then q<=GPIO_0(2 downto 0); else q<= "000"; end if; end process; end bufferwithGpio_arc;Honored Contributoruse a counter
