Added UNTESTED version of spi-commands-lost detection.

[fpga/rpi-motor-control.git] / pmsm-control / div128.vhdl

diff --git a/pmsm-control/div128.vhdl b/pmsm-control/div128.vhdl
new file mode 100644 (file)
index 0000000..b63d1dd
--- /dev/null
+++ b/pmsm-control/div128.vhdl
@@ -0,0 +1,46 @@
+-- provides frequency division by 12
+-- initialy intended to make 4.17Mhz from 50Mhz 
+
+library ieee;
+use ieee.std_logic_1164.all;
+use ieee.numeric_std.all;
+use work.util.all;
+
+entity div128 is
+
+port (
+       clk_in: in std_logic;
+       rst: in std_logic;
+       fail_safe: out std_logic
+);
+end div128;
+
+
+architecture behavioral of div128 is
+       signal count : std_logic_vector (6 downto 0);
+       signal rst_prev: std_logic;
+begin
+       
+       
+       seq : process 
+       begin
+               wait until (clk_in'event and clk_in='1');
+               rst_prev <= rst;
+               if rst='1' and rst_prev='0' then
+                       count <= "0000000";
+                       fail_safe <= '0';
+               else
+                       count <= std_logic_vector(unsigned(count) + 1);
+               end if;
+               
+               if count = "1111111" then
+                       fail_safe <= '1';
+               else 
+                       fail_safe <= '0';
+               end if;
+       end process;
+
+       
+               
+end behavioral;
+