FAQ
How do I get access to the testbed ?
This is explained on the Getting Started page
I can't create links to/from nodes in the City of Things testbed in JFed.
We are painfully aware of this limitation, and fixing this is at the top of our list of priorities.
How do I know which serial interface (/dev/ttyUSBX) is connected to what device?
If you use one of the 'CoT' Disk Images, symlinks are automatically created in '/dev' that will allow you to identify each serial port:
- OpenUSB:
/dev/ttyOPENUSB - EZRUSB@433 MHz:
/dev/ttyEZR433 - EZRUSB@868 MHz:
/dev/ttyEZR868 - EFM32GG+LoRa:
/dev/ttyLORA
By referring to these symlinks instead of the /dev/ttyUSBX-devices directly you can be sure that you are talking to the correct device.
If you are not using one of the 'CoT' images, you can add the necessary udev-rules needed to to do by copying /etc/udev/rules.d/50-persistent-usb.rules from one of the 'CoT' images to your own image.
How can I flash/erase the EZRUSB devices ?
If you use one of the 'CoT' Disk Images, the EZRUSB devices can be programmed using the flash_ezr script.
This script can be invoked as follows:
flash_ezr <device> <elf-file>
Where:
<device>is one of 'EZR433' or 'EZR868', depending on whether you want to flash the 433MHz or 868MHz device<elf-file>is the ELF-image to flash to the device.
Likewise, the erase_ezr script can be used to erase an EZRUSB device. This script is invoked in exactly the same way as the flash_ezr script, except that no ELF-image file is specified.
Even if you are not using one of the 'CoT' images, you are strongly advised to use the flash_ezr and erase_ezr scripts since these scripts contain the logic required to ensure that the 'correct' device is flashed/erased.
You can add these scripts to your own image by simply copying them from the /usr/local/bin directory from one of the 'CoT'-images to your own image, but to run them OpenOCD (0.9.0 or later) does need to be installed.
How can I flash/erase the LoRa device ?
The 'LoRa' device is basically a Giant Gecko starter kit equipped with an RFM95W LoRa module. (See [Node Specifications]). This module is equipped with an on-board J-Link debugger, so debugging/programming/erasing this board is done in exactly the same way as it is for any other SiLabs MCU. (See here for the offical 'Getting Started' guides.
To make things a bit easier, all 'CoT' disk images already contain the necessary J-Link software as well as a few helper scripts.
Flashing the 'LoRa'-device can be done using the flash_lora script.
This script is invoked as follows:
flash_lora <device> <elf-file>
Where:
<elf-file>is the ELF-image to flash to the device.
Likewise, the erase_lora script can be used to erase the 'LoRa-'device. This script is invoked in exactly the same way as the flash_lora script, except that no ELF-image file is specified.
If you are not using one of the 'CoT'-images, you first need to install the J-Link Software And Documentation Pack for your specific operating system. Once this package is installed you can add the flash_lora and erase_lora scripts to your image to make flashing and erasing the device a bit easier. These scripts can be found in the /usr/local/bin directory in any of the 'CoT' disk images.
I have a question and I can't find the answer on the Wiki
Please send your question to . We'll be happy to help you along and update the documentation where necessary.