start dt

.gitignore

@@ -14,4 +14,6 @@ driver/*.mod.c
 driver/*.mod.o
 driver/*.o
 driver/modules.order
+dtoverlay/*.dtbo
+
 

dtoverlay/Makefile

@@ -0,0 +1,26 @@
+# Source and target file names
+DTS = counter.dts
+DTBO = counter.dtbo
+
+# Installation paths
+OVERLAY_DIR = /boot/overlays
+CONFIG_TXT = /boot/firmware/config.txt
+OVERLAY_NAME = counter
+
+all: $(DTBO)
+
+$(DTBO): $(DTS)
+	dtc -@ -I dts -O dtb -o $@ $<
+
+install: $(DTBO)
+	sudo cp $(DTBO) $(OVERLAY_DIR)/
+	@if ! grep -q "^dtoverlay=$(OVERLAY_NAME)$$" $(CONFIG_TXT); then \
+		echo "dtoverlay=$(OVERLAY_NAME)" | sudo tee -a $(CONFIG_TXT); \
+	else \
+		echo "Overlay already present in config.txt."; \
+	fi
+	@echo "Installation complete. Reboot your Raspberry Pi to activate the overlay."
+
+clean:
+	rm -f *.dtbo
+

dtoverlay/counter.dts

@@ -0,0 +1,24 @@
+/dts-v1/;
+/plugin/;
+
+/ {
+    compatible = "brcm,bcm2835";
+
+    fragment@0 {
+        target = <&gpio>;
+        __overlay__ {
+            gpio_led_blue: gpio_led_blue {
+                brcm,pins = <26>;
+                brcm,function = <1>; // output
+                brcm,pull = <0>;     // no pull
+            };
+
+            gpio_led_red: gpio_led_red {
+                brcm,pins = <21>;
+                brcm,function = <1>; // output
+                brcm,pull = <0>;     // no pull
+            };
+        };
+    };
+};
+