160. Building the iotinator master module
This is the first iotinator master module with a proper case.
It does not have a GSM board yet, and for now, no backup battery although the charging circuit is there, and there is room for the battery. I still have to test powering the ESP while the battery is charging, using an ESP-01 board that does not have a Vbat or Vin pin (unlike wemos boards).
Here I'm using an ESP-01, which is the smallest ESP8266 board I found that I flashed successfully (for now). It's rather appropriate to handle the master module, since it does not need that many I/O. Of course, it might be different when GSM handling is ready (or it could use RX/TX for that...). Also, an analog input would be nice to monitor battery level and warn when main power goes out.
The first phase is to position the components and boards to get an idea of the volume you will need. You'll have to think about what the case should include, and very importantly, how to mount the board in the case, making sure no part comes in the way of final mounting
Here is the last of a series of positioning attempts:
Once reasonably sure you didn't forget anything, or some space is left for what you have in mind, time to heat up your soldering iron.
Test it before going any further. You probably don't want to go through the trouble of casing a board if is not working.
Measuring it (preferably with a caliper) will allow you to select a case or design and print one.
Enclose it in the case you have selected or designed. Here I'm using a custom design, which is usually the best solution to have something that really suits your needs in terms of dimension of course, but also inside features to support the screen, board, etc.
Christmas time !!
Close it...
...And you are done.
TODO !
It's the case that mostly needed some post processing.
The screen holders, which were fine on the oled panel prototype, were too big, probably due to printing settings of 4 outline shells.
The screen could be 1mm closer to the case surface, here it's a little too deep.
I set up the case wall thickness to 2mm which is unnecessary. I'll lower it to 1.3mm and gain printing time.
Next step is to make some tests with a backup battery, to have it charging in normal conditions, and providing power when main power is out.
Done! It was a bit tight :)
Next, design a PCB to build the module with discreet CMS components instead of the ready made tiny boards (like USB TTL, battery charging, power adaptation) I used for the prototype.