See this Blog Post for details.
This repository contains the source code, as well as, the source code to distribute the tool which requres GNU Autotools to build. If you just want to run the tool I recommend just getting the tarball below where you can build from source.
This code has also been run on a Pine64 and Orange Pi Zero.
We're going to assume you have 2 E32 Modules attached to two Raspberry PIs. Thus, one can transmit and the other receive and vice-versa. Details for each step in the Blog Post.
- Wire up your E32 module. We require 3 pins. Two for the Mode pins and 1 for the Aux Pin. See section below to change wiring if needed.
- Using
raspi-configconfigure your Serial Port, Unix groups and UART File Permissions. - Install the
e32command line tool. See below. - Read the version and status from the
./e32 --status. If this doesn't work the next one won't. - Do an end-to-end test to transmit from one and receive on the other. See below.
wget http://lloydrochester.com/code/e32-1.10.2.tar.gz
tar zxf e32-1.10.2.tar.gz
cd e32-1.10.2
./configure
make
sudo make install
e32 --help
e32 --status
The wiring defaults to:
RPi Pin 23 -> E32 M0 (Input)
RPi Pin 24 -> E32 M1 (Input)
RPi Pin 18 -> E32 AUX (Output)
We can change the wiring two ways:
- Specify pins on the command line. For example
e32 --m0 27 --m1 22 --aux 17. - For a more permanent solution we can change the build to have different defaults. This can be done by doing
CFLAGS="-DGPIO_M0_PIN=27 -DGPIO_M1_PIN=22 -DGPIO_AUX_PIN=17" ./configureon the installation. Now the defaults will be permanently changed
If we used option #2 to build in the defaults we can view them by doing a e32 -h and the default pin will be printed out.
Again we assume you have two E32 modules attached to two different Raspberry Pi modules.
Run e32 on both at the same time, no options are needed. In one terminal type something and hit enter. This will transmit what was typed. On the other terminal you should see what you typed. By doing this what you typed when through the UART to one E32, was transmitted, received by the other E32, read out the other UART and was output onto the terminal. Now do this in the other direction.
The tool offers more than just taking input from a keyboard. It's meant to run as a daemon and run in the background. If, however, you don't run it as a daemon you can send files and/or save to a file.
When running as a daemon communication to and from the e32 is via Unix Domain Socket. This allows other tools written an any language to communicate wirelessly by just sending and receiving from a socket. See the blog post for an example in Python.
If you don't want the tarball you could build using the GNU Autotools.
# clone this repo
./autogen.sh # this creates the configure script and Makefiles
./configure
make
We can use the -w HEX option to change settings. For example we could save the settings by doing a e32 -w C000001A1744. See the datasheet for each of these options. For the form XXYYYY1AZZ44. If XX=C0 parameters are saved to e32's EEPROM, if XX=C2 settings will be lost on power cycle. The address is represented by YYYY and the channel is represented by ZZ.