WiPy on the home network

Heiko RuppOctober 27th, 2015Last Updated: October 27th, 2015

0 45 2 minutes read

Recently there was a Kickstarter about “an Arduino that runs Python”, the WiPy. This is a small IoT board with WiFi on it (which is not available on stock Arduinos) for an attractive price. And being able to use a high level language along with a lot of existing libraries makes it attractive too.

A few days ago I got the WiPys that I backed and the first obstacle to get the running was the power supply as they do not have a (micro) USB connector on board (and I also did not back the extension boards they offered).

Luckily I still had an old defunct USB hub from which I could solder out the connector and put it on a small PCB for this purpose (while doing that exercise I also found out that the 5V of the USB port are allowed to be 4.75-5.25V and on the end of a hub even being as low as 4.4V).

WiPy on Breadboard with USB power supply connector.

Now that the WiPy is on the breadboard, I set up my computer to scan for the WLAN of the WiPy and then telneted into the device. I poked around and tried to inspect the WLAN settings as described in the manual:

>>> from network import WLAN
>>> wlan = WLAN() # we call the constructor without params

This immediately made the connection drop. It turned out I needed to first update the firmware to the latest version (v1.1 at time of the writing), which was painless (but a bit confusing, as they also supply a bootloader.bin, that is not needed).

After the firmware upgrade the above worked and I tried to change the device to talk to my home network. The caveat here is that at the moment you issue

1	`wlan.init(WLAN.STA)`

to put the machine into station mode (default is being an access point), the connection drops. Some users have solved that by connecting via UART and serial line, but I did not really want to go that route.

Instead I edited boot.py on my local computer and then uploaded it via ftp into /flash. I found out, that if you don’t terminate the ftp client and have a telnet connection open as well, I could easily (syntax) check the uploaded file by pressing Ctrl-D in the terminal:

MicroPython v1.5-1-ge954604 on 2015-10-21; WiPy with CC3200
Type "help()" for more information.
>>>    <control-D>   <-- here
PYB: soft reboot
Traceback (most recent call last):
  File "boot.py", line 17, in 
NameError: name not defined

The WiPy tells me that there is an error in my file, so I edit it locally and upload it again via the ftp connection. And only at the end when the WiPy is happy, I press the hard-reset button.

Now for reference my boot.by that worked for me:

from network import WLAN
 
SSID = 'home_SSID'         # SSID of your home network
AUTH = (WLAN.WPA2, 'very_secret') # WPA secret as 2nd param
IP = '10.1.2.42'           # Fixed IP the device should get
ROUTER = '10.1.2.3'        # IP of your router
DNS = '10.1.2.3'           # IP of your DNS server
NETMASK = '255.255.255.0'  # Netmask to use
 
import machine
 
wlan = WLAN()
 
if machine.reset_cause() != machine.SOFT_RESET:
    wlan.init(WLAN.STA)
    # configuration below MUST match your home router settings!!
    wlan.ifconfig(config=(IP, NETMASK, ROUTER, DNS))
 
if not wlan.isconnected():
   wlan.connect(ssid=SSID, auth=AUTH, timeout=5000)
   while not wlan.isconnected():
      machine.idle() # save power while waiting
   print('WLAN connection succeeded!')