Updated sample for new APIs.

js/dac/dac.js

@@ -1,36 +1,41 @@
+// See https://youtu.be/saIGmyrM_Wc for details, starting around 6:00.
+// We create an R-2R ladder using data bits A7, A6, A4, B3, B2, C3 and GND.
+
+let eventLoop = require("event_loop");
 let gpio = require("gpio");
-let pins = ["PA7", "PA6", "PA4", "PB3", "PB2", "PC3"];
-for (let i=0; i<pins.length;i++) {
-  gpio.init(pins[i], "outputPushPull", "none");
+
+let pins = [gpio.get("PA7"), gpio.get("PA6"), gpio.get("PA4"), gpio.get("PB3"), gpio.get("PB2"), gpio.get("PC3")];
+for (let i = 0; i < pins.length; i++) {
+  pins[i].init({ direction: "out", outMode: "push_pull" });
 }
 
 function reset() {
-  for (let i=0; i<pins.length;i++) {
-    gpio.write(pins[i], false);
+  for (let i = 0; i < pins.length; i++) {
+    pins[i].write(false);
   }
 }
 
 let delay_ms = 2000;
 while (true) {
-    // 0b100000 / 0b111111 * 3.3 = 1.65 volts
-    print("1.65 volts");
-    reset();
-    gpio.write(pins[5], true); 
-    delay(delay_ms);
+  // 0b100000 / 0b111111 * 3.3 = 1.65 volts
+  print("1.65 volts");
+  reset();
+  pins[5].write(true);
+  delay(delay_ms);
 
-    // 0b101010 / 0b111111 * 3.3 = 2.2 volts
-    print("2.2 volts");
-    reset();
-    gpio.write(pins[5], true); 
-    gpio.write(pins[3], true); 
-    gpio.write(pins[1], true); 
-    delay(delay_ms);
+  // 0b101010 / 0b111111 * 3.3 = 2.2 volts
+  print("2.2 volts");
+  reset();
+  pins[5].write(true);
+  pins[3].write(true);
+  pins[1].write(true);
+  delay(delay_ms);
 
-    // 0b010011 / 0b111111 * 3.3 = 1.0 volts
-    print("1.0 volts");
-    reset();
-    gpio.write(pins[4], true); 
-    gpio.write(pins[1], true); 
-    gpio.write(pins[0], true); 
-    delay(delay_ms);
+  // 0b010011 / 0b111111 * 3.3 = 1.0 volts
+  print("1.0 volts");
+  reset();
+  pins[4].write(true);
+  pins[1].write(true);
+  pins[0].write(true);
+  delay(delay_ms);
 }