adding Zig examples

EXAMPLES_Zig/jetgpio_PWM_example.zig

@@ -0,0 +1,45 @@
+// Usage example of the JETGPIO library
+// Compile with: zig build-exe jetgpio_PWM_example.zig -ljetgpio -lc
+// Execute with: sudo ./jetgpio_PWM_example
+
+const std = @import("std");
+const jetgpio = @cImport({
+    @cInclude("jetgpio.h");
+});
+
+pub fn main() !void {
+    const init = jetgpio.gpioInitialise();
+
+    if (init < 0) {
+        std.debug.print("Error initiating jetgpio: {}\n", .{init});
+        std.process.exit(1);
+    }
+
+    // Setting up PWM frequency=10kHz @ pin 32
+
+    const PWMstat = jetgpio.gpioSetPWMfrequency(32, 10000);
+    if (PWMstat < 0) {
+        std.debug.print("PWM frequency set up failed. Error code:  {}\n", .{PWMstat});
+        std.process.exit(1);
+    }
+
+    // Set up PWM duty cycle to approx 50% (0=0% to 256=100%) @ pin 32
+
+    const PWMstat2 = jetgpio.gpioPWM(32, 128);
+
+    if (PWMstat2 < 0) {
+        std.debug.print("PWM start failed. Error code:  {}\n", .{PWMstat2});
+        std.process.exit(1);
+    }
+
+    var x: i32 = 0;
+    std.debug.print("PWM going at pin 32 for 60 seconds\n", .{});
+
+    while (x < 30) {
+        std.time.sleep(2000000000);
+        x += 1;
+    }
+
+    // Terminating library
+    jetgpio.gpioTerminate();
+}