An ultra low-power STM32 µC with on-board RF module for wireless sensor nodes
- Final build with rev4 PCB, works as intended, available in the shop
- Design files are in the hardware area of the Embello Git repository
- The core Mecrisp Forth software files can be found in the ezr area
There are three headers on the JeeNode Zero: a 17-pin main header (left), a 6-pin FTDI header (bottom), and a 5-pin AUX header (bottom right):
The top of the JNZ is the unpopulated side. Most components are on the bottom.
Many - but not all - pins can support a (digital) input voltage level up to 5.5V. All output voltage levels are between 0V and 3.3V.
Power is normally applied to either of the 5V pins (they are internally tied together on the PCB). If the supply voltage is between 3.4V and 5.5V, the JeeNode Zero will run at its nominal 3.3V design level. However, with proper clock confiuration, a lower voltage can also be applied, since the µC and RF module can both work down to 1.8V.
If a 3V coin cell is fitted, power should not be applied to any of the supply pins - one solution is to always remove the coin cell when connecting to FTDI.
Top and bottom view¶
The top of the JeeNode Zero is unpopulated by default:
The bottom has the wireless radio module, the micrcontroller, and the power supply regulator:
The boards above are shown with the FTDI header mounted in the recommended “in-line” position, but the header can also be mounted upwards or downwards.
Most recent first:
A wireless rotary encoder - weblog, Mar 2017
- Post-mortem of a bug
- Connecting a rotary encoder
- Cutting the rotary cord
- Making an always-on device
- Several years on a coin cell?
The JeeNode Zero rev4 - weblog, Feb 2017
- Getting started with a JNZ
- Installing more drivers in flash
- Setting up a remote node
- How all those JNZs are tested
Various JNZ developments - weblog, Feb 2017
The upcoming JNZ rev4 - weblog, Feb 2017
Let’s have some fun with a JNZ - weblog, Dec 2016
- Hey, there’s a radio in there!
- Ultra low-power and coin cells
- A high-resolution sensor node
- Remote development over WiFi
The upcoming JeeNode Zero - weblog, Dec 2016