migrate from Travis to GHA and rework examples (#78)

* migrate from Travis to GHA

* rework examples

1 files changed, 35 insertions, 0 deletions

diff --git a/examples/icezum/blink.vhdl b/examples/icezum/blink.vhdl
new file mode 100644
index 0000000..81c32ed
--- /dev/null
+++ b/examples/icezum/blink.vhdl
@@ -0,0 +1,35 @@
+library ieee;
+use ieee.std_logic_1164.all;
+use ieee.numeric_std.all;
+
+entity blink is
+  port (
+    clk : in std_logic;
+    led0, led1, led2, led3, led4, led5, led6, led7 : out std_logic
+  );
+end blink;
+
+architecture synth of blink is
+  signal blink: std_logic;
+begin
+  process (clk)
+    variable cnt : unsigned (23 downto 0);  -- 3_000_000 requires 24 bits
+  begin
+    if rising_edge(clk) then
+      if cnt = 2_999_999 then
+        cnt := x"000000";
+        blink <= not blink;
+      else
+        cnt := cnt + 1;
+      end if;
+    end if;
+  end process;
+  led0 <= blink;
+  led1 <= blink;
+  led2 <= blink;
+  led3 <= blink;
+  led4 <= blink;
+  led5 <= blink;
+  led6 <= blink;
+  led7 <= blink;
+end synth;