Perhaps the final post about the good old nRF24L01+ and the shady Chinese suppliers that tend to optimize all freakin’ bits and pieces. This time I will tell how to create a simple RF calibration station to verify the modules are properly operational and how to manually fix those that are not.
This time I was spending the holidays as usual away from the city, further improving my smarthome. This time I was installing a bunch of devices with nRF24L01+ radios. When I was running out of spare nRF24L01+ modules, I noticed that I was left with a bunch of weird modules that kind of work, but really crappy. They feature huge packet losses, but whenever you touch the PCB antenna, it goes away. I decided to look into the problem and document my findings.
(more…)
I recently got a nice batch of nrf24l01 modules dirt cheap (~55 cent per module). If anybody wondered if you could cost-optimize these modules even more… Well, turns out you can. They won’t be quite working, but who cares? A detailed analysis of what those folks actually ‘optimized out’ is just under the cut.
It was a busy month, but I finally managed to find a minute and update the rf24boot. Yes, the very thing that can push firmware updates via nRF24L01 wireless modules. Along is a regular bunch of updates to rf24 library in antares. One of the big news I finally took some 20 minutes and layed out a proper programming dongle. Since I didn’t have a cheap stm32 with usb around, and stm32f103ret6 looked like an overkill for this purpose this dongle still uses avr, vusb, but has a 16M (20M is possible as well) crystal. The lengthy changelog’s under the cut, but it’s big.
Apparently I’ve come up to a point, when I want to do firmware upgrades for my home automation ‘over-the-air’. Since I’m using nRF24L01 dongles, I decided to write a bootloader for that.
While my pet antares project is slowly progressing towards the 0.2-rc2 release (honestly, really slowly), I’ve added the nice and shiny RF24 library (A port of maniacbug’s arduino library to pure C with no arduino dependences) to interface with nrf24L01 2.4Ghz dongles. I also fixed a few nasty race conditions out there on the way, but those are totally a different story.
So, what’s inside:
