Posts on ATTNode

Running AttNode v1/v2 on TTN v3

Thu, 02 Sep 2021 00:00:00 +0000

As you will probably know, the legacy TTN v2 Stack will be shut down in December of this year, which means nodes on TTN v2 should be migrated to The Things Stack Community Edition (formerly known as TTN v3 Stack). Unfortunately, the TTS stack made it a little harder to run “incomplete” nodes like the AttNode v1 and v2, which in the default firmware don’t support downlink packets, and are therefore not exactly LoRaWAN Spec compatible.

HM330x Sleep Fixes and SPS30 Support

Thu, 08 Jul 2021 00:00:00 +0000

The AttNode v3 firmware now has support for the Sensirion SPS30 Particulate Matter Sensor . At the moment the PM1, PM2.5, PM4 and PM10 values in µg/m³ are reported by the sensor. There is only support for the I2C-Mode for now. Since the Sensor needs a 5V power supply, you’ll need a power source that can provide that (e.g. USB), and connect the ATTNode via a PowerPack. the I2C-Pins of the Sensor can be directly connected to the ATTNode

Support for HM330x Particulate Matter Sensor

Mon, 03 May 2021 00:00:00 +0000

The AttNode v3 firmware now has support for the HM3301 particulate matter sensor from Seeed Studios . At the moment the PM1, PM2.5 and PM10 values in µg/m³ for atmospheric environment will be added to the payload if the sensor is connected and enabled.

The sensor can be connected to the regular I2C-pins (Vin, GND, SCL, SDA) and will run from a 3.3V power source. Be aware that the sensor can use up to 120mA of current, so your power source has to be able to provide at least 250mA (combined current of the sensor and the RFM95W while sending).

ATTNode v3 CO2 Sensor Addon and Multisensor support

Sun, 28 Mar 2021 00:00:00 +0000

grauzone has created an ATTNode v3 addon board for the MH-Z19C CO2 Sensor. The addon has an onboard 3,3V voltage regulator to supply the node while providing the needed 5V to the sensor (directly from a 5V supply). It also incorporates 2 WS2812B RGB LEDs to signal current LoRa status as well as the current CO2 Level. Details on the hardware can be found on Github .

While adding the code for the CO2-Sensors I also extended the firmware to support multiple sensors. For example a BME280 and a CO2-Sensor can be added in parallel. See the README.md in the Firmware Repository for further details on how to use it.

ATTNode v3 Firmware Now Uses PlatformIO

Mon, 01 Feb 2021 00:00:00 +0000

Recently PlatformIO added support for the Microchip ATTiny3216 used on the ATTNode v3. Starting today, all further development of the official firmware will use PlatformIO as the coding environment instead of Arduino IDE, because of the far better IDE, sensible library management and automated project configuration.

The old Arduino IDE variant of the firmware is archived as a separate branch arduinoide in the Git repository for reference purposes, but any new development will use the PlatformIO variant.

ATTNode Addon: Powerpack

Fri, 08 Jan 2021 00:00:00 +0000

grauzone has developed a simple voltage regulator board to make more power sources usable for the ATTNode:

Overview

This is an add-on for the ATTNode to supply it with operating voltages between 3.5-16V. The voltage source must provide at least 120 mA. The PCB has the format of the CR2032 battery clip and is soldered to the back of the node instead of the clip. This allows the node to be powered by a USB power supply, a LiPo or any other fixed voltage power supply. Here are some pictures of the add-on:

ATTNode v3 Set Send Interval via Downlink

Sun, 20 Dec 2020 00:00:00 +0000

In the newest revision of the ATTNode v3 firmware it is now possible to change the send interval at runtime using LoRa Downlink packets. This makes it possible to remote-configure nodes without reflashing them.

To set a sending interval it has to be scheduled as a downlink paket for the node as a 2-Byte uint value. To set an interval of 10 minutes for example, one has to send the value 0x000A (10 as a 2-Byte Hex), for 5 minutes it would be 0x0005 and so on. If you want to reset the node to the compiled in value just send 0xFFFF. Here is an example setting the interval to 10 at the TTN-Console:

ATTNode v3 Case and SHT21 Support

Fri, 04 Dec 2020 00:00:00 +0000

An adapted 3D-printable case for the ATTNode v3 is now available. Here is a first look of it (on the left in white) next to the case of an ATTNode v2:

Also the Firmware now supports the SHT21 Sensor in addition to the BME280.

ATTNode v3 Minimal Firmware Available

Wed, 02 Dec 2020 00:00:00 +0000

Since yesterday evening there is a first minimal firmware for the ATTNode v3 Available in the Git Repository . This Firmware does support the basic functionality of the Node as in:

Uses the MCCI LoRa LMIC for maximum LoRaWAN compatibility
Uses OTAA for Device Activation
Supports DeepSleep between Measuring/Sending for Maximum Power Savings
Implements the BME280 Sensor

As there is no support for the ATTiny3216 in PlatformIO yet, the firmware uses ArduinoIDE with the MetaTinyCore for the time being. Some hints about Configuring the ArduinoIDE are in the Repo. When PlatformIO Support becomes available for the 3216 I will switch to using it again as it has been with the ATTNodes v1/v2.

ATTNode v3 Hardware Finished

Thu, 26 Nov 2020 00:00:00 +0000

Today the final Prototypes of the ATTNode v3 arrived and where successfully tested for basic functionality. With this I have now added the ATTNode v3 to the Site. Firmware is still in the very early stages at the moment, but the Hardware should work as expected. See the ATTNode v3 subpage for more info.

TinyLoRa is now ATTNode

Thu, 10 Sep 2020 00:00:00 +0000

Today I announce the renaming of the TinyLoRa project to ATTNode which is short for ATTiny Node. Reason for this is, that “LoRa” is a regsitered trademark of Semtech, which means that I could get into legal trouble using it for my “product”. Since I don’t have the time or money for a legal battle with a big corporation, I have decided to preemptively rename the project.

The website will be located at www.attno.de from now on, but www.ttgw.de will be forwarded to the new one for the forseeable future.

Measuring Brightness with a LED

Thu, 14 May 2020 00:00:00 +0000

twentysixer has developed a simple but effective way to detect brightness with the TinyLoRa. All that is needed is a simple LED:

With the TinyLoRa and a simple led you can detect brightness and darkness.

The LED is connected to 2 GPIOs in the reverse direction. The LED is charged and measured until it is discharged again. The darker it is, the longer it will take to discharge it. Clear LEDs with a low forward voltage are best suited, e.g. red or yellow

Deep Sleep Current and Optimizing the BME280

Thu, 23 Apr 2020 00:00:00 +0000

Since the TinyLoRa Node does seem to get some interest in the last days the question of power consumption and deep sleep currents came up a few times. So here are some measurements I took as well as a way to potentially more than halve the deep sleep current when using one of the usual BME280 sensor modules.

Deep Sleep Current Measurements

I use the ATTiny84s deep sleep / powerdown feature and the internal watchdog to keep the power consumption low and get a useful battery life with a CR2032. To get an idea how good/bad this works I did some measurements. i

Test Arrangement	Deep Sleep Current
TinyLoRa without a Sensor	~ 4.4µA
TinyLoRa with BME280 Module (Stock)	~ 10.7µA
TinyLoRa with BME280 Module (modified)	~ 4.5µA

LoRa FrameCounter now Saved Across Reset/Power Loss

Tue, 21 Apr 2020 00:00:00 +0000

Up until now the Lora Frame Counter, which is a security feature to prevent replay attacks, was reset every time the ATTiny rebooted (e.g. because of reset or power loss). Because of this the Frame Counter Check in the settings of the Lora devices had to be disabled, or messages after a reset wouldn’t be processed by the TTN Backend.

I have now implemented a way to save the Frame Counter in the ATTinys integrated EEPROM, so it will survive resets and power loss. Because of that the Frame Counter Check can now be left enabled when using the current Firmware (starting from git commit 361f8e0b85). Please be aware that the EEPROM is reset when flashing the ATTINY, therefore you will have to reset the frame counter in the TTN-Console when reflasing a device with enabled Frame Counter Checks.

TinyLoRa v2 Case Available

Mon, 13 Apr 2020 00:00:00 +0000

3D-Printable Case for TinyLora v2 Available

As promised I have now also designed a 3D-Printable case for the TinyLoRa v2 Boards. The Board is meant to be used with a small coil antenna directly mounted to the PCB. Here are some pictures:

The STL and OpenSCAD files are available from the ATTNode v2 main page

TinyLoRa v2 Prototype Tests Successfull

Sun, 08 Mar 2020 00:00:00 +0000

My tests with the v2 prototype PCBs where successfull, I did not find any functional issues with the boards, and only some minor cosmetic issues.

Documentation of the TinyLoRa v2 PCB is now available on this site . You can also find a ZIP with the Gerberfiles attached there, so you can order your own from the usual PCB prototyping companies.

TinyLoRa v2 First Prototype PCBs Arrived

Thu, 27 Feb 2020 00:00:00 +0000

After a long wait due to coronavirus outbreaks in China and resulting delays in the PCB production it is finally here, The first prototype of the TinyLoRa v2 Board:

The triple use footprint for u.fl, SMA and wire antenna seems to work as intended, and the rest of the board works as before. So all in all a sucessfull first prototype run.

TinyLoRa v2 Combo Antenna Port

Sun, 26 Jan 2020 00:00:00 +0000

Some more development on the TinyLoRa v2 board. I have modified the SMA connector footprint in such way, that it should now be possible to also use a U.FL Connector or use a Wire- or Coil Antenna instead of the SMA edgemount connector. With this change it should be possible to use all of the most common types of antennas with the node. I also did some more cleanup and finishing touches:

TinyLoRa v2 Development started

Fri, 24 Jan 2020 00:00:00 +0000

Here is a sneak peek at the next iteration of the TinyLoRa PCBs. I got it down to roughly half the size compared to the v1 board by making it a two sided board and putting the battery holder, which is by far the biggest component, onto the Backside. I also added the possibility to use a edge-mounted SMA connector for the antenna.

Because of the battery at the back the sensors don’t fit there anymore, so the GPIO-connector was flipped by 180° so the sensor now mounts over the front of the board. There are still some finishing touches to be done before I will put them into production, but it shouldn’t be to much work. As I don’t have any real boards yet here are some renders from KiCAD: