ESP32 Boot Camp

… for me.

I got a rando e-mail offering me “free parts” and I usually don’t even bother opening the e-mail. It’s ALWAYS garbage right? Well, maybe I hadn’t slept well the night before but I opened it. (psss. You can scroll down about a page before I actually get anywhere in this post…)

What was I thinking? I hovered carefully over the link… seemed pretty safe… short-ish domain ended with a .com .. not extra stuff on the end… OK. They got me. The website was http://digitspace.com — It seemed like an electronics website so I e-mailed. Back…. going back and forth they seem to be running some kind of promotion or perhaps they are trying to build some brand recognition getting bloggers to give them some advertising. In the end selected $50 worth of parts that consisted of two ESP32 micro dev boards that had WiFi (of course), LoRa, OLED display and and extra LED. There was some switch button types but they were a bit more and for some reason I didn’t think I needed them. Well a week later these things actually showed up (and I didn’t have to give them my credit card or paypal info!).

OK THE START..

A week later the boards showed up in the mail.. they look and feel reasonable and they came with some sample firmware that proved they worked. Unfortunately the site did not include any documentation… but I did the “hardwork” for you if you want to follow along… but let’s start with the end… So far I am here:

First thing first I had to add ESP32 support to my Arduino IDE.. I dropped this in the “additional board manager URLs”:

https://dl.espressif.com/dl/package_esp32_index.json

See how in this quick video..

I found a simple tx-rx LoRa code off the internet but I won’t share because it took too much re-work to get working on my board. So I took it’s essience …

I had to add these libraries:

Add libraries:
Adafruit SSD1306 by Adafruit
Adafruit GFX Library by Adafruit
LoRa by Sandeep Mistry

(all came right off the normal library manager)

I couldn’t find an OLED library that worked until reading some and found I liked this one that seemed to be the “best for me”:
https://github.com/osresearch/esp32-ttgo

After that it was smooth sailing. My code is work-in-progress towards my final project. It can be found here: https://github.com/chasihler/TTGO-OLED-RX-TX-HTTP-PUT

Inspiration along the way:

Battery Monitoring: https://github.com/YogoGit/TTGO-LORA32-V1.0

A nice post, read too late, had the correct pinout/board of many different but similar boards: http://brettbeeson.com.au/ttgo-lora-esp32-v2-1-r1-6/

Putting your ESP32 to sleep:
https://randomnerdtutorials.com/esp32-deep-sleep-arduino-ide-wake-up-sources/

My findings were similar … though I haven’t ACCURATELY measured it my USB analyzer says 50mA on and 10mA off.. no peak readings yet but I can live with 10mA in my project.

Vacation Tidbits

I’ve returned from vacation and brought back a ton of tidbits to share over the next few weeks.

I left the beautiful Pacific Northwest to work on my ranch house in Meade County, South Dakota. I had a number of projects I hoped to complete while there and got through a fair portion of my list that was mostly filled with “wishful thinking” mini-projects. Not all of these are electronics based but bear with me, there are some items of interest.. no guarantee it’s you who is interested though 🙂 I also hit up an AM site with one of my best friends and scored some goodies!

Water: My artesian well has low flow, this isn’t crippling but it can be a hassle. I’ve installed a water tank with a float that allows the well to fill a tank through a 3/4″ in-ground sprinkler solenoid. When pressure drops and the well booster pump kicks on it sucks every bit of water it can including any air it can find out of a contentiously flowing drain into a stock tank a couple hundred feet down the line. Now I’ll have a reservoir to provide extra water on the fly and filter some slight sand in the water supply.

Pump and Water Tank in the basement
Pump and Water Tank in the basement

Sewer: I had a collapsed sewer line… talk about the shits! 😀 I thought this was about all I would get done on my vacation as I was going to have to hand dig the line.. it was about 12 wide, 5 foot down. Luck day, I had a good friend stop by and helped me out a bit… that took off a few minutes of rockin’ the shovel.

0198aeb478ff8d171bb83efe889e5a6d8550ffb0df

With all that work out of the way I had some time to meet up with a friend at an AM broadcast site while he was performing some maintenance. I used to apprentice under him but ended up going a different career route. Not sure I made the right choice some days?

I grabbed my Rigol spectrum analyzer (you bring yours with you on vaca as well, right?) and threw a piece of wire into the input about a hundred feet away from the tower… the station is on 810KHz AM.

 

KBHB_wide

marker was obviously not on the peak on the reading above.

KBHB_2

I took a ton of readings, compared mine to a much more expensive SA (very satisfied with the results) as well as taking some readings on a 948MHz STL transmitter.

I scored a nice directional sampling line and a bunch of SMA connectors with coax, a 20 watt digital OTA cable transmitter and a ton of other little goodies while I was at it. I great score. I got a VCXO, some filters, attenuators and just a ton of stuff I’ll check out here and there.

0146ba8c3dea244962dd8398f1370519501a121397

AM Antenna

AM Transmitter

Finally, I’ve got some video to edit and drop on the YouTube channel as well but I’ll get to that in the coming days.