MicroPython Forum (Archive)

Hi there!

I was lucky enough to receive one of the first, hand assembled WiPy boards to review.
I have been having trouble getting the board to run, however; I have connected power to the vin and ground to ground, however after a second the heartbeat starts to flash rapidly; the WiPy does not appear to connect to it or anything.

After reading the WiPy general info it would appear there could be an error with the python script.
I tried the suggested reset by connecting GPIO28 to the 3.3v OUT pin, but it did not affect the heartbeat as it should.

Could someone please let me know if i am going mad/being incredibly stupid and am missing something?

Thanks guys

Craig

Hi Craig!

Before sending the WiPy your way I was testing the UART and the SD card (and that requires a few lines of code in the boot.py), and now without the SDcard connected the script might fail, however, you should still be able to see the 'wipy-wlan' network and connect to it. I have a few questions:

1. How is your power supply (between 3.6 and 5.5V)? And it must be able to supply pulses of 200mA.
2. Were you ever able to connect to the WiPy?
3. Did you put your own boot.py? If so, please paste it here so I can check it. The API is still work in progress, and some things might have changed...
4. How are you trying to go into safe boot? You need to tie GPIO28 to 3v3, reset, wait for the heart beat LED to flash slowly, then fast, and after that you can disconnect GPIO28 from 3v3. Doing that it will skip execution of any script that might be crashing the WiPy.

After trying safe boot, do you see the 'wipy-wlan' network?

Thanks for the swift reply Dani!

You nailed it with question 1 - while I was waiting for a reply i tried some different sources of power and have identified the issue as a faulty 5v power supply - not supplying enough current. I now have a working 5v power supply attached and have a much more regular heartbeat, and can also see the network.
Time to play - I'm so bliddy excited I'm like a kid at Christmas!

You are welcome!

I am glad to hear that it's working now! I have the Blynk (www.blynk.cc) library in progress. Feel free to check it out and give it a try!

https://github.com/danicampora/wipy/blo ... k/blynk.py

Cheers,
Daniel

OH MY DAYS - blynk looks tremendous!!
I'm planning a little project to fully test the WiPy for my review; I'm going to put it inside a Wall-e Toy and use a L298N motor driver board to run some motors and potentially add some servos for arm/head control... Using Blynk to add a nice user interface would make a great remote control for it!
I'm looking forward to getting it running; I've done a few Arduino-based wall-e builds but they have been crying out for Web-integration rather than Bluetooth. I'm definitely planning on getting my hands on the SD Card add- on shields so i can add sound effects and suchlike (I usually hack the original Wall-e Board to trigger sounds but that sucks )

I just received my 5 WiPys and must say that I have trouble getting them into reliable operation.

First of all, it is difficult to get solid soldering connections to any headers due to the kind of finish on the outside holes. I had to apply SMD flux before getting acceptable soldering joints.

Second, the WiPy seems to be very picky in terms of power supply. I first tried a 1,5 V to 5 V step-up converter in order to power the WiPy from a single 1.5 V cell. This did not work; the LED just kept on flashing fast. One can also see a drop in the 3.3 V pin by ca. 1 V every few seconds with the help of an oscilloscope. I suppose the Wifi component requires a lot of peak current when sending.

With a 5 V supply from a lab power supply, I was able to get the WiPy working.

With a bigger buffer cap of 470 uF, the 1,5 V to 5 V step-up converter **seems**, i.e. the flashing goes away and the "heart beat" LED blinks slowly same as with the lab power supply. Unfortunately, the Wifi connection is still very unreliable.

What shall I do?

First of all, it is difficult to get solid soldering connections to any headers due to the kind of finish on the outside holes. I had to apply SMD flux before getting acceptable soldering joints.

We hand soldered more than 2000 WiPy's ourselves and we never had to use flux, just good quality multicore soldering wire...

Yes, there are current peaks of a few hundred milliamps for short periods during Tx.

Is your step up converter capable of supplying those current peaks? Based on:

One can also see a drop in the 3.3 V pin by ca. 1 V every few seconds with the help of an oscilloscope

I would say it can't. You just need a better supply. It's not that it's picky, WiFi needs those current peaks specially when in AP mode.

mhepp wrote:I just received my 5 WiPys and must say that I have trouble getting them into reliable operation.

mhepp wrote:What shall I do?

If you can't get them to work as intended feel free to send them my way

A step-up converter from 1.5 to 5V seems "ambitious" in this context. Say the WiPy briefly demands 300mA. Even if the converter were 100% efficient the battery demand will be 300*5/1.5 = 1A. In practice it will be more. I'd study the spec for the battery you're using, as well as that for the converter before expecting this to work.