PWM using FPGA

[iceman]

does anyone have a code for this? i will be using pwm for controlling
a servo motor..

 

[Leon Heller]

does anyone have a code for this? i will be using pwm for controlling
a servo motor..

There is some VHDL code for driving model control servos in "Rapid
Prototyping of Digital Systems" by Hamblen and Furman. It's on the CD-ROM
that comes with the book.

Leon

 

[Jonathan Bromley]

There is some VHDL code for driving model control servos in "Rapid
Prototyping of Digital Systems" by Hamblen and Furman. It's on the CD-ROM
that comes with the book.

My colleague Bert Cuzeau has done a nice description of simple
motor control techniques:
http://www.alse-fr.com/English/ApNote204189.pdf

and a Google search through the comp.lang.vhdl archives will
turn up several discussions of the same topic.

 

[krithika211]

spwm using fpga

hi i am doing a project fpga based speed control of ac servomotor using SPWM.i need the vhdl coding for this. someone please help.

 

[jeppe]

Actually do you have two choises - PWM and PPM

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

ENTITY PWM_vs_Sigma_Delta_v2 is
    generic( N:   natural := 4;
	          Max: natural := 16);
    Port ( Clk :  in  STD_LOGIC;
	        Scale: in  STD_LOGIC;
           PCM :  in  STD_LOGIC_VECTOR (N-1 downto 0);
           PWM :  out  STD_LOGIC;
           PPM :  out  STD_LOGIC);  -- or SD
end PWM_vs_Sigma_Delta_v2;

ARCHITECTURE Behavioral of PWM_vs_Sigma_Delta_v2 is
   signal PWM_Count:  STD_LOGIC_VECTOR (N-1 downto 0) := (others=>'0');
   signal Sigma: 		 STD_LOGIC_VECTOR (  N downto 0) := (others=>'0');
   signal Delta: 		 STD_LOGIC_VECTOR (  N downto 0) := (others=>'0');
	signal Scaled_clk: STD_LOGIC;	
begin

   process( Clk, Scale)
		variable Scalex:	     integer;
		constant Scale100msek: integer   :=   1; --5000;
		constant Scale500msek: integer   :=   0; --25000;
		variable Count:  integer range 0 to 50000001 := 0;
	begin	   
	   if Scale='1' then
         Scalex := Scale100msek; 
		else 
         Scalex := Scale500msek;
		end if;
		
	   if rising_edge(Clk)then
			if Count>=Scalex then
			   Scaled_clk <= '1';
				Count      := 0;
			else
			   Scaled_clk <= '0';
				Count      := Count+1;			
			end if;
		end if;
   end process;
	
	PWM_Generator: process( Clk, PWM_Count, PCM)
	begin
	   if rising_edge(Clk) then
		   if Scaled_Clk='1' then
			   if PWM_Count<Max-1 then
		         PWM_Count <= PWM_Count+1;
				else
               PWM_Count <= (others => '0');	
            end if;					
			end if;
		end if;
	   
	   if PWM_Count<PCM then
		   PWM <= '1';
		else
		   PWM <= '0';
		end if;
	end process PWM_Generator;	
	
	Delta <= '0'&PCM;	
   Sigma_Delta_Generator: process( Clk)
	begin
	   if rising_edge(Clk) then
		   if Scaled_Clk='1' then
				if Sigma<Max then
					PPM   <= '0';
					Sigma <= Sigma+Delta;	
				else
					PPM   <= '1';
					Sigma <= Sigma+Delta-conv_std_logic_vector(Max,N+1);
				end if;
			end if;
		end if;
	end process Sigma_Delta_Generator;	
		
end Behavioral;

The simulations can be seen here as well:
http://www.jjmk.dk/MMMI/Exercises/05_Counters_Shreg/No7_PWM_vs_SigmaDelta/index.htm
Your welcome
Jeppe

 

[krithika211]

fpga vhdl

hi thanks a lot for the help.but i am stil a bit confused about this code.is it vhdl code to generate SPWM signals? i have not learnt vhdl programming that is why i am unable to figure out what exactly the code is for.in my project i have to generate Sine PWM (SPWM) signals using vhdl to control speed of ac servomotor.is it possible for u to give ur email id?i may need your help.

 

[PRASAD84]

hi im doing project on pwm control of bldc motor using FPGA

hi i am doing a project fpga based speed control of ac servomotor using SPWM.i need the vhdl coding for this. someone please help.

hi krithika im also doing project on fpga.
i have some pwm codes. it is better if we discuss about our projects .reply me at
please give me ur mail id also
prasadpabolu gmailcom
my mobile no +91 9952586864
my mail id is prasadpabolu at the rate of gmail dot com
please give me reply

 

[necostefan]

hi, i have too a project like yours(a pwm control of BLDC motor using FPGA) and i don't have the code for it.Please help me if you have something.Cosmin

 

[subhash_iitr]

I am beginner in FPGA design. I want to interface ADC no: AD7822 to virtex-5 (ML-505) kit externally.The ADC -AD7822 is a parallel ADc .Please guide me in doing this and perovide me the VHDL code for interfacing parallel ADC.
Thanks

 

[[email protected]]

hi to all
my project is to control the position of AC servo motor by sliding mode control can anybody guide me how to proceed and how i get the VHDL/verilog code for same help me if possible
thanks in advance

 

[mera]

hi everyone
please please please take attention to my letter
my project is to control dc motor by using fpga so i want from you to help me with the vhdl code as soon as you can i hope if you can next week
thanks