Add test

flake.nix

@@ -49,6 +49,20 @@
           default = self.packages.${system}.smi;
         };
 
+        checks = {
+          simple =
+            pkgs.runCommand "test"
+              {
+                # Goes up to 7
+                NIX_DEBUG = 0;
+              }
+              ''
+                mkdir -p $out
+                ${self.packages.${system}.tt-gcc}/bin/riscv32-unknown-elf-gcc ${./tests/test.c} -o $out/test
+                ${self.packages.${system}.tt-gcc}/bin/riscv32-unknown-elf-gcc -mblackhole ${./tests/test.c} -o $out/test-wormhole
+              '';
+        };
+
         formatter = pkgs.nixfmt-rfc-style;
       }
     );

tests/test.c

@@ -0,0 +1,31 @@
+#define GPIO_BASE (0x48000000U) // Base address for GPIO port (e.g., GPIOA on STM32)
+#define RCC_BASE  (0x40021000U) // Base address for RCC (Reset and Clock Control)
+
+#define RCC_AHB2ENR (*(volatile unsigned int *)(RCC_BASE + 0x4C))
+#define GPIOA_MODER (*(volatile unsigned int *)(GPIO_BASE + 0x00))
+#define GPIOA_ODR   (*(volatile unsigned int *)(GPIO_BASE + 0x14))
+
+#define LED_PIN 5 // Assume the LED is connected to GPIO pin 5
+
+void delay(volatile unsigned int count) {
+    while (count--);
+}
+
+int main(void) {
+    // Enable the clock for GPIOA
+    RCC_AHB2ENR |= (1 << 0); // Enable GPIOA clock
+
+    // Set GPIOA pin 5 to output mode (01)
+    GPIOA_MODER &= ~(3 << (LED_PIN * 2)); // Clear mode bits for pin 5
+    GPIOA_MODER |=  (1 << (LED_PIN * 2)); // Set mode to 01 (output)
+
+    while (1) {
+        // Toggle the LED
+        GPIOA_ODR ^= (1 << LED_PIN);
+
+        // Delay
+        delay(100000);
+    }
+
+    return 0;
+}