Search found 69 matches

by Mike Teachman
Sat Mar 30, 2019 3:50 am
Forum: ESP32 boards
Topic: How to turn off WiFi in async MQTT?
Replies: 20
Views: 929

Re: How to turn off WiFi in async MQTT?

Is this a reasonable way to operate? Good point. Just turning of the WiFi radio is quite harsh. Turning off the WiFi radio to save some mA is the ultimate end goal. Would it be possible to somehow signal one of the mqtt_as tasks to first disconnect from the broker, then turn off WiFi. Perhaps a new...
by Mike Teachman
Thu Mar 28, 2019 7:27 pm
Forum: ESP32 boards
Topic: How to turn off WiFi in async MQTT?
Replies: 20
Views: 929

Re: How to turn off WiFi in async MQTT?

This feature was never intended thanks for the background design motivations for async mqtt. That totally makes sense - it does a really good job at keeping broker and wifi connections. but as you are using loboris fork, why don't you use his own mqtt library implementation that is using threads? I...
by Mike Teachman
Thu Mar 28, 2019 4:58 pm
Forum: ESP32 boards
Topic: How to turn off WiFi in async MQTT?
Replies: 20
Views: 929

How to turn off WiFi in async MQTT?

I'm hoping to get some help on a thorny problem I can't easily solve... background: I am using Async MQTT with the Lobo port to publish sensor data to a remote broker, every 15 minutes. This asyncio MQTT implementation solves a major requirement in my application - publishing sensor data without blo...
by Mike Teachman
Mon Mar 18, 2019 2:32 pm
Forum: ESP32 boards
Topic: Introducing the TinyPICO
Replies: 5
Views: 558

Re: Introducing the TinyPICO

Congratulation you guys ! This is looking really good. Registered for the sale... One suggestion on a photo: how about a top-down photo showing the module plugged into a breadboard? perhaps better than a country-specific coin for trying to illustrate the compact module size? Is it possible to releas...
by Mike Teachman
Tue Mar 05, 2019 6:18 am
Forum: Drivers for External Components
Topic: TI ADS1219 ADC driver
Replies: 8
Views: 593

Re: TI ADS1219 ADC driver

You can hardly achieve 24-bit resoulution. ADS1219 is a delta-sigma ADC, and the actual (effective) resolution depends on voltage reference, the sample time and the overall circut design. See the section 7.1 in the datasheet for more details. ADS1219 has an internal voltage reference of 2.048V. If ...
by Mike Teachman
Tue Mar 05, 2019 6:11 am
Forum: Drivers for External Components
Topic: TI ADS1219 ADC driver
Replies: 8
Views: 593

Re: TI ADS1219 ADC driver

If it is a 24bit ADC and your Vref is 3.3v then the sensitivity it has to read is 3.3v/(2**24) = 0.00000019669532775878905 volts What sort of hardware would be needed to decouple and isolate the ADC so that such fine voltages are not just inducted from the air?? For this ADC the useful resolution i...
by Mike Teachman
Sun Mar 03, 2019 8:34 pm
Forum: Drivers for External Components
Topic: TI ADS1219 ADC driver
Replies: 8
Views: 593

Re: TI ADS1219 ADC driver

At this time there is no low-cost breakout board available for this device. It is possible to make your own - I added a section to the github repo listing the parts I used.

https://github.com/miketeachman/micropy ... kout-board

ads1219-breakout.jpg
ads1219-breakout.jpg (20.38 KiB) Viewed 504 times
by Mike Teachman
Sat Mar 02, 2019 12:57 am
Forum: Drivers for External Components
Topic: TI ADS1219 ADC driver
Replies: 8
Views: 593

TI ADS1219 ADC driver

If you need a 24-bit ADC here is a driver for the Texas Instruments ADS1219

https://github.com/miketeachman/micropython-ads1219

All device functions are supported in this driver. Tested with uPy v1.10 running on ESP32 port.

datasheet:
http://www.ti.com/lit/ds/symlink/ads1219.pdf
by Mike Teachman
Wed Feb 13, 2019 4:41 pm
Forum: ESP32 boards
Topic: i2s compatibility
Replies: 10
Views: 1185

Re: i2s compatibility

I have some questions though, why you decimate or prune your samples before saving into the SD?. And, how can I achieve full resolution (18bits) from the mic (https://cdn-shop.adafruit.com/product-files/3421/i2S+Datasheet.PDF)? There is now a better way to save full resolution mic samples to extern...
by Mike Teachman
Sun Feb 10, 2019 4:12 am
Forum: ESP32 boards
Topic: i2s compatibility
Replies: 10
Views: 1185

Re: i2s compatibility

thanks for trying it out. Really glad to know it works on someone else's build ! For the pruning part, I reduced the sample size to 16 bits to reduce the time to copy the samples to the SDCard (which should help to support a higher sampling rate), and to reduce the space used on the SDCard. In my ap...