This is a brief overview of the OTA (Over The Air) firmware updating procedure for BLE112 or BLE113 systems equipped with the required hardware for OTA updates (like our BLE113 breakout board). This procedure (and our BLE113 breakout board) strictly follows Bluegigas APP NOTE for OTA updating.
This is my custom board incorporating an ATMEGA 328p MCU, lipo battery charger with USB connector for charger powering, 8MHz crystal oscillator, lipo battery powered, SPI programming header and header for a 1.8" SPI TFT display.
The device is for my "Bubba Keg", a creation made for a few friends. Essentially it is a control system for the 70oz Bubba Keg insulated mugs. It uses an ultrasonic sensor in the lid to determine quantity and a PTC thermistor in the cup to determine content temperature. For the old design I used a custom PCB that joined an Arduino Nano and 1.8" TFT display. It ran off a 9v battery and was housed in a generic enclosure. it was far more bulky than I wanted it to be. That is why I went for a SoC solution.
The display has gauges for quantity, temperature and voltage. The display also shows you calculated L/Hr consumption rate and time to empty.
Programming the ATMEGA without USB support was the challenge, but I found some tutorials on using another arduino (UNO) as an ISP (In Service Programmer). I wired the two together and used the Arduino IDE to program the chip. I was very pleased to see it working! Not having the bootloader on the chip means it starts up lightning fast and has more room for programming space. I chose 8MHz to conserve power as it was more important than performance.
Next step will be to custom design and 3D print a nice compact enclosure for it and test fit it on a mug!
Seems I wasn't immune to having the plastic high/ low speed gear (p/n P0704212) strip on me. I crashed the mill in low gear cutting steel. It was hard enough to rotate the head about 20 degrees.
Grizzly was good enough about supplying me one under warranty and I purchased an extra one for good measure.
I believe I know a contributing factor to the gears stripping at least slightly before they should. I initially chalked it up to poor rigging as the low gear did not engage 100% of its tooth width. The more I looked at it however I realized there is no possible way to adjust the gear mesh quality and it does not engage 100% in low or high gear.
A possible solution would be to re manufacture the arm of the high/ low speed fork arm. If you were to make the fork arm p/n P0704217 a little longer than it currently is it would allow you to have more throw on either end of the travel, allowing the gears to mesh completely.
Another option would be to make another detent plate (item 273 on the left) with the detents located further apart. I am not sure if something else limits the throw of the knob but I do not remember being able to rotate it past the detents.
Since I already have the CNC mill (G0704) in the shop, the next logical choice was a 3D printer. I wanted something relatively affordable yet capable. I went with a MendelMax 1.5 Deluxe kit from 3D Factory LLC.
My free time is limited but I felt the value of having built it from scratch was worth the extra time vs. buying assembled.
I am already well versed in Arduino and CNC in general so I feel I am at an advantage to most, time will tell!
Prices in US Dollars