Interface and Application Programming
Assignments
individual assignment:
-write an application that interfaces a user with an
input &/or output device that you made
group assignment:
-compare as many tool options as possible
Research
throughout the week
Group Work
group site link
Microcontroller Html based beserver
Pros
* Low cost: Microcontrollers are generally cheaper than full-fledged computers, making them an attractive option for simple web server applications.
* Low power consumption: Microcontrollers are designed to be low-power devices, which can be an advantage in applications where power consumption is a concern.
* Customizability: With a microcontroller, you have full control over the hardware and software, allowing you to tailor your web server to your specific needs.
* Reliability: Microcontrollers are often used in industrial and embedded applications, where reliability is a critical requirement. They are designed to be robust and durable.
Cons:
* Limited resources: Microcontrollers have limited processing power, memory, and storage compared to full-fledged computers. This can limit the complexity of the web server and the number of concurrent users it can support.
* Limited connectivity: Microcontrollers may not have built-in networking capabilities or may only support limited networking protocols. This can limit the types of devices and networks that can connect to the web server.
* Limited software support: Microcontrollers often use proprietary software development environments and may have limited support for third-party software libraries and frameworks.
* Security concerns: Microcontrollers may not have the same level of security features and protections as full-fledged computers, making them potentially vulnerable to attacks.
Overall, using a microcontroller to host a web server can be a good choice for simple, low-traffic applications where cost and power consumption are concerns. However, more complex applications with higher traffic and security requirements may require a full-fledged computer or server.
Setting up a web server.
The first step this week was to set up a web server to host an interface that I designed. To do this at the suggestion of fellow Fab Academy student Adam Stone I followed the tutorial linked above to learn how to host a web server on a raspberry pi pico W. Following this and uploaded the code it says to right here.
import network
import socket
import time
from machine import Pin
led = Pin(15, Pin.OUT)
ssid = 'YOUR NETWORK NAME'
password = 'YOUR NETWORK PASSWORD'
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(ssid, password)
html = """<!DOCTYPE html>
<html>
<head> <title>Pico W</title> </head>
<body> <h1>Pico W</h1>
<p>%s</p>
</body>
</html>
"""
max_wait = 10
while max_wait > 0:
if wlan.status() < 0 or wlan.status() >= 3:
break
max_wait -= 1
print('waiting for connection...')
time.sleep(1)
if wlan.status() != 3:
raise RuntimeError('network connection failed')
else:
print('connected')
status = wlan.ifconfig()
print( 'ip = ' + status[0] )
addr = socket.getaddrinfo('0.0.0.0', 80)[0][-1]
s = socket.socket()
s.bind(addr)
s.listen(1)
print('listening on', addr)
# Listen for connections
while True:
try:
cl, addr = s.accept()
print('client connected from', addr)
request = cl.recv(1024)
print(request)
request = str(request)
led_on = request.find('/light/on')
led_off = request.find('/light/off')
print( 'led on = ' + str(led_on))
print( 'led off = ' + str(led_off))
if led_on == 6:
print("led on")
led.value(1)
stateis = "LED is ON"
if led_off == 6:
print("led off")
led.value(0)
stateis = "LED is OFF"
response = html % stateis
cl.send('HTTP/1.0 200 OK\r\nContent-type: text/html\r\n\r\n')
cl.send(response)
cl.close()
except OSError as e:
cl.close()
print('connection closed')
With this code I changed the SSID to my hotspot name and the password to the password, and it connected to it allowing it to host a web server. Here is a picture of the running site.
After looking through the code to understand how it works I realised that the actual websitet of HTML which I am confident in and can code in. So I quickly changed some stuff to see if it would even change by changing this part of the code.
<html>
<head> <title>Pico W</title> </head>
<body> <h1>Pico W</h1>
<p>%s</p>
</body>
</html>
And made it into my name just to see if any changes happened and here is a picture of the site after.
After changing this I looked into the output this code has where by changing the link you can turn on and off an LED as shown here in the console here.
But I did not like having to put the link in so using my HTML knowledge I added buttons you could click by changing the html part of the code to this.
html = """<!DOCTYPE html>
<html>
<head> <title>Pico W</title> </head>
<body> <h1>Pico W</h1>
<h3>%s
<br>
<br>
Use the button below to turn on the LED.
<br>
<button onclick="location.href='/light/on'">Turn On LED</button>
<br>
<button onclick="location.href='/light/off'">Turn Off LED</button>
<br>
<br>
<br>
Make sure that your LED works before trying this because it keeps failing for me because the LED was burned out.
</h3>
</body>
</html>
'''
<br>
By changing it to this I added two buttons that when clicked will automatimatically change the sites link. This caused the site too look like this.
And here is a video of the site working.
Setting up the LED
The next step was to actually hook it up to an LED or another output device. To do this I just uploaded the whole code shown below onto the board making the led in the code connect up to the on-board LED to show the final product.
import network
import socket
import time
import machine
from machine import Pin
led = Pin('LED', Pin.OUT)
ssid = 'Smc'
password = 'stuart7459'
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(ssid, password)
html = """<!DOCTYPE html>
<html>
<head> <title>Pico W</title> </head>
<body> <h1>Pico W</h1>
<h3>%s
<br>
<br>
Use the button below to turn on the LED.
<br>
<button onclick="location.href='/light/on'">Turn On LED</button>
<br>
<button onclick="location.href='/light/off'">Turn Off LED</button>
<br>
<br>
<br>
Make sure that your LED works before trying this because it keeps failing for me because the LED was burned out.
</h3>
</body>
</html>
"""
max_wait = 10
while max_wait > 0:
if wlan.status() < 0 or wlan.status() >= 3:
break
max_wait -= 1
print('waiting for connection...')
time.sleep(1)
if wlan.status() != 3:
raise RuntimeError('network connection failed')
else:
print('connected')
status = wlan.ifconfig()
print( 'ip = ' + status[0] )
addr = socket.getaddrinfo('0.0.0.0', 80)[0][-1]
s = socket.socket()
s.bind(addr)
s.listen(1)
print('listening on', addr)
# Listen for connections
while True:
try:
cl, addr = s.accept()
print('client connected from', addr)
request = cl.recv(1024)
print(request)
request = str(request)
print(request)
led_on = request.find('/light/on')
led_off = request.find('/light/off')
print( 'led on = ' + str(led_on))
print( 'led off = ' + str(led_off))
if led_on > 1:
print("led on")
led.value(1)
stateis = "LED is ON"
if led_off > 6:
print("led off")
led.value(0)
stateis = "LED is OFF"
response = html % "Recieved"
cl.send('HTTP/1.0 200 OK\r\nContent-type: text/html\r\n\r\n')
cl.send(response)
cl.close()
except OSError as e:
cl.close()
print('connection closed')
And here is a video of the final project working.
Summary
This week I learned how to host a web server from a raspberry pi pico w and connect to it over the internet. If possible I would love it if I could add this to my final project so that I can control it too my phone but that will be a later addition if I can finish early. This was a really good skill to learn and I plan to keep messing with it. If I do anything interesting I will doccument below otherwise that is what I learned from this week.