Improve examples for Lattice iCEstick

- move "leds" examples to subdirectory
- add Makefile
- add *.json files to .gitignore
- adjust README.md and fix some typos

1 files changed, 41 insertions, 0 deletions

diff --git a/examples/icestick/leds/multi2.vhdl b/examples/icestick/leds/multi2.vhdl
new file mode 100644
index 0000000..78bf298
--- /dev/null
+++ b/examples/icestick/leds/multi2.vhdl
@@ -0,0 +1,41 @@
+architecture multi2 of leds is
+  signal clk_4hz: std_logic;
+  signal clk_5sec : std_logic;
+begin
+  process (clk)
+    --  3_000_000 is 0x2dc6c0
+    variable counter : unsigned (23 downto 0);
+  begin
+    if rising_edge(clk) then
+      if counter = 2_999_999 then
+        counter := x"000000";
+        clk_4hz <= '1';
+      else
+        counter := counter + 1;
+        clk_4hz <= '0';
+      end if;
+    end if;
+  end process;
+
+  process (clk)
+    variable counter5 : unsigned (4 downto 0);
+  begin
+    if rising_edge (clk) then
+      clk_5sec <= '0';
+      if clk_4hz = '1' then
+        if counter5 = 19 then
+          clk_5sec <= '1';
+          counter5 := "00000";
+        else
+          counter5 := counter5 + 1;
+        end if;
+      end if;
+    end if;
+  end process;
+
+  led1 <= clk_5sec;
+  led2 <= '0';
+  led3 <= '0';
+  led4 <= '0';
+  led5 <= '0';
+end multi2;