add pmod_leds demo

Author: wuxx

demo/pmod3_music2a.bin

@@ -0,0 +1,23 @@
+filename = led
+pcf_file = led.pcf
+
+ICELINK_DIR=$(shell df | grep iCELink | awk '{print $$6}')
+${warning iCELink path: $(ICELINK_DIR)}
+
+build:
+	yosys -p "synth_ice40 -blif $(filename).blif" $(filename).v
+	arachne-pnr -d 5k -P sg48 -p $(pcf_file) $(filename).blif -o $(filename).asc
+	icepack $(filename).asc $(filename).bin
+
+prog_flash:
+	@if [ -d '$(ICELINK_DIR)' ]; \
+        then \
+            cp $(filename).bin $(ICELINK_DIR); \
+        else \
+            echo "iCELink not found"; \
+            exit 1; \
+    fi
+
+
+clean:
+	rm -rf $(filename).blif $(filename).asc $(filename).bin

src/basic/verilog/pmod_leds/Makefile

@@ -0,0 +1,11 @@
+set_io CLK    35
+
+set_io LED[0] 45
+set_io LED[1] 43
+set_io LED[2] 38
+set_io LED[3] 36
+set_io LED[4] 46
+set_io LED[5] 44
+set_io LED[6] 42
+set_io LED[7] 37
+

src/basic/verilog/pmod_leds/led.pcf

@@ -0,0 +1,23 @@
+//plug pmod-led on PMOD2
+
+module switch(input CLK, output [7:0] LED);
+      
+    reg [25:0] counter;
+    wire lclk = counter[22];
+
+    initial begin
+        LED = 8'b11111110;
+    end
+
+    always @(posedge CLK)
+    begin
+        counter <= counter + 1;
+    end
+
+    always @(posedge lclk)
+    begin
+        LED <= {LED[6:0], LED[7]};
+    end
+
+
+endmodule