Iterating for better ch9 code.

ch-9/3-sensors/sensor.html

@@ -11,7 +11,9 @@
       .attr("y", 20)
       .text("--");
     
-    d3.json("sensors").then(function(data) {
-      d3.select("#left_dist").text(data['left_distance'])  
-    });
-</script>
+    setInterval(function() {
+      d3.json("sensors").then(function(data) {
+        d3.select("#left_dist").text(data['left_distance'])  
+      });
+    }, 300);
+</script>

ch-9/3-sensors/sensor_remote.py

@@ -1,9 +1,3 @@
-# .deploy/send-it.sh \
-#   ch-9/3-sensors/sensor_remote.py \
-#   ch-9/3-sensors/robot_wifi.py \
-#   ch-9/3-sensors/robot.py \
-#   ch-9/3-sensors/pio_encoder.py \
-#   ch-9/3-sensors/sensor.html
 import json
 
 from adafruit_esp32spi import adafruit_esp32spi_wsgiserver
@@ -18,7 +12,7 @@ app = WSGIApp()
 def index(request):
   with open("sensor.html") as fd:
     hello_html = fd.read()
-  return 200, [('Content-Type',"text/html")], hello_html
+  return 200, [('Content-Type',"text/html")], [hello_html]
 
 @app.route("/sensors")
 def sensors(request):
@@ -27,7 +21,7 @@ def sensors(request):
   }
   robot.left_distance.clear_interrupt()
 
-  return 200, [('Content-Type', 'application/json')], json.dumps({sensor_data})
+  return 200, [('Content-Type', 'application/json')], [json.dumps(sensor_data)]
 
 print("Setting up wifi.")
 wifi, esp = robot_wifi.connect_to_wifi()
@@ -49,13 +43,15 @@ ip_int = ".".join(str(int(n)) for n in esp.ip_address)
 print(f"IP Address is {ip_int}")
 while True:
     try:
-        server.update_poll()
+        try:
+          server.update_poll()
+        except RuntimeError as e:
+          print(f"Server poll error: {type(e)}, {e}")
         # background task
     except:
         print("Shutting down wifi on failure. resetting ESP")
         wifi.reset()
         raise
-
 # Reader exercise
 # add the right distance to the distance sensor remote. Consider where to position the meter for this, how to return both sensors in 
 # the sensors call. Don't forget to clear the interrupt to get new readings.

ch-9/4-teleop/teleop.html

@@ -21,25 +21,38 @@
     ]
   }
 
-  function move_robot(point) {
-    d3.json("/control", {
-      method:"POST",
-      body: JSON.stringify({
-        "move": point
-      }),
-      headers: {
-          "Content-type": "application/json; charset=UTF-8"
-      }
-    });
+  var last_position = [0, 0];
+  var new_position = false;
+
+  function move_robot() {
+    if (new_position === true) {
+      d3.json("/control", {
+        method:"POST",
+        body: JSON.stringify(last_position),
+        headers: {
+            "Content-type": "application/json; charset=UTF-8"
+        }
+      }).finally(function() {
+        setTimeout(move_robot, 10) // continue the lop 50 ms after a response, even a non-positive one.
+      });
+      new_position = false;
+    }
+    else {
+      setTimeout(move_robot, 10); // continue the loop if there's nothing to send
+    }
   }
 
   function stop() {
-    move_robot([0, 0]);
+    last_position = [0, 0];
+    new_position = true;
   }
 
+  setTimeout(move_robot, 50); // start the control loop
+
   circle.on("pointermove", function() {
       if(d3.event.buttons == 1) {
-        move_robot(circle_to_relative(d3.mouse(this)));
+        last_position = circle_to_relative(d3.mouse(this));
+        new_position = true;
       }
     })
     .on("mouseup", stop)

ch-9/4-teleop/teleop.py

@@ -1,11 +1,7 @@
-# .deploy/send-it.sh \
-#   ch-9/4-teleop/sensor_remote.py \
-#   ch-9/4-teleop/robot_wifi.py \
-#   ch-9/4-teleop/robot.py \
-#   ch-9/4-teleop/pio_encoder.py \
-#   ch-9/4-teleop/sensor.html
 import json
 import time
+from digitalio import DigitalInOut
+import board
 
 from adafruit_esp32spi import adafruit_esp32spi_wsgiserver
 from adafruit_wsgi.wsgi_app import WSGIApp
@@ -24,16 +20,24 @@ state = State()
 def index(request):
   with open("teleop.html") as fd:
     hello_html = fd.read()
-  return 200, [('Content-Type',"text/html")], hello_html
+  return 200, [('Content-Type',"text/html")], [hello_html]
 
-@app.route("/move", methods=["POST"])
-def movement(request):
-  movement = json.loads(request.body)
-  robot.set_left(movement['y'] + movement['x'])
-  robot.set_right(movement['y'] - movement['x'])
+@app.route("/control", methods=["POST"])
+def control(request):
+  movement = json.load(request.body)
+  print(f"Received movement: {movement}")
+
+  robot.set_left(-movement[1] + movement[0])
+  robot.set_right(-movement[1] - movement[0])
   state.stop_at = time.time() + 1
+  return 200, [('Content-Type',"application/json")], ["true"]
 
 print("Setting up wifi.")
+status_led = DigitalInOut(board.LED)
+status_led.switch_to_output()
+status_led.value = False
+
+
 wifi, esp = robot_wifi.connect_to_wifi()
 server = adafruit_esp32spi_wsgiserver.WSGIServer(
   80,
@@ -45,17 +49,29 @@ print("Starting server")
 
 server.start()
 ip_int = ".".join(str(int(n)) for n in esp.ip_address)
+
+status_led.value = True
+
 print(f"IP Address is {ip_int}")
 while True:
     try:
+        status_led.value = False
         server.update_poll()
+        status_led.value = True
         # background task
         if state.stop_at < time.time():
           robot.stop()
+    except RuntimeError as e:
+      print(f"Server poll error: {type(e)}, {e}")
+      robot.stop()
+      print(f"Resetting ESP...")
+      wifi.reset()
+      print("Reset complete.")
     except:
-        print("Shutting down wifi on failure. resetting ESP")
-        wifi.reset()
-        raise
+      print("Shutting down wifi on failure. resetting ESP")
+      robot.stop()
+      wifi.reset()
+      raise
 
 # Reader exercise
 # Can you combine the sensors and the control app? Can you think about how to control it using the sensors for feedback.