LoRa Discovery Kit

[Tesla DeLorean]

Posted on April 05, 2017 at 22:40

 

 

LoRa Discovery Kit

 

STM32L072 and LoRa Discovery Kit featuring Open LoRa module by Murata using STM32L072CZY6TR MCU

 

http://www.st.com/en/evaluation-tools/b-l072z-lrwan1.html

 

Features

 

• Ultra-low-power STM32L0 Series MCUhttp://www.mouser.com/stm32l0, Cortex® -M0+ based with 192Kbytes of Flash memory, 20Kbytes of RAM, 6Kbytes of EEPROM, LCD, crystal-less USB, T-RNG, PCROP
• 157dB maximum link budget
• +20dBm, 100mW constant RF output versus Vsupply
• +14dBm high efficiency PA
• Programmable bit rate up to 300kbps
• High sensitivity: down to -137dBm
• Bullet-proof front end: IIP3 = -12.5dBm
• 89dB blocking immunity
• Low RX current of 10mA, 200nA register retention
• Fully integrated synthesizer with a resolution of 61Hz
• FSK, GFSK, MSK, GMSK, LoRa™ and OOK modulations
• Built-in bit synchronizer for clock recovery
• Sync word recognition
• Preamble detection
• 127dB+ dynamic range RSSI
• Built-in temperature sensor and low battery indicator 1.65V to 3.6V power supply

 

The AT_Slave example (creates AT modem via ST-LINK VCP) is about 41KB in size

 

• Attached is original shipping firmware (April 2017) Ping-Pong Demo
• Added LoraDisco_ATSlave_US915.hex a build of the example from the Cube Extensions, USA 915 MHz option selected
• Added LoraDisco_ATSlave_US915_V111.hex a build from the V1.1.1 tree
• Added LoraDisco_ATSlave_US915HYBRID_V111.hex
• a build from the V1.1.1 tree w/US915_HYBRID (17-Aug-2017)
• Added LoraDisco_ATSlave_US915HYBRID_FULL_NOT_TINY_V111.hex.zip a build using Keil native sscanf/printf w/AT+SEND fixed

 

[Tesla DeLorean]

Posted on September 01, 2017 at 05:09

LRWAN successfully ported to assorted STM32L4 boards using the SX1272 shield

NUCLEO-L476RG

NUCLEO-L496ZG

B-L475E-IOT01A

https://community.st.com/0D50X00009XkgY0SAJ

The Grasshopper boards also arrived today, shipped very quickly/efficiently. The 5 dBi antennas arrived as well.

[Tesla DeLorean]

Posted on September 01, 2017 at 22:25

Ported code to the Grasshopper, had to change TCXO enable to PH1.

PB13 is LED

Schematic looks to be wrong, SWDIO is D8, SWCLK is D9

DFuSe 3.05 doesn't seem to work properly with the STM32L0

USART2 works on PA2/PA3, hooked that up for debug telemetry, equivalent to B-L072Z-LRWAN1 discovery board.

[SARTHAK KELAPURE]

Posted on January 24, 2018 at 06:44

By TCXO enable, you need to say TCXO_VCC? Is it?

[Tesla DeLorean]

Posted on September 08, 2017 at 23:42

Murata module will also support SigFox with forthcoming firmware

http://www.murata.com/en-us/about/newsroom/news/product/frontend/2017/0718

Update, Andrew caught the release of the software

https://community.st.com/0D70X000006SsniSAC

http://blog.st.com/x-cube-sfox-firmware-sigfox/

http://www.st.com/en/embedded-software/x-cube-sfox.html

[T J]

Posted on September 10, 2017 at 04:16

I haven't used RF comms before, our target markets have facilities usually spread over a km.

I use other Murata parts on my board, do you think their solution is the best to start with ?

I take forever to code my work, I'd like to start with the right solution. Price is not that important, but choosing the wrong platform could be a disaster.

'Currently, Murata’s Type ABZ LoRaWAN™ module, which uses a STMicro STM32-based wireless microcontroller and SX1276 Semtech RFIC, operates in the 806 930MHz frequency band and provides a nominal output power of +14 dBm that can be boosted to +20 dBm for long range or poor signal location applications' I checked the Aust RF allocation chart. too many colors for me... it looks like it is fully allocated.. for mobiles, and ISM ?

in an industrial situation, what range would you expect through concrete walls ?

how do you work through a steel building ? with analogue repeaters or would you run a cable through to a repeating node ??

could you clarify:

which is the best solution to start with for 1km industrial applications ?

I would hope and expect they use spread spectrum RF.

Encryption, is it standard on board or do we have to implement it ourselves ?

[Tesla DeLorean]

Posted on September 10, 2017 at 21:13

Behaviour is highly situational, you'd have to evaluate the technologies in the environment you expect to deploy. I'm working in concrete slab construction industrial/warehouse type buildings, though that's not my target environment. Building penetration at 915 MHz or 433 MHz is going to be significantly better than 2.4 GHz.

I can get 1KM driving within the local business park, with a 5dBi antenna mounted about 5ft above ground in the window of my office. With a better antenna on the truck side, I got around 3KM LoS, this is was without selecting more conservative encoding and spreading settings. I would do better with the antenna mounted 25ft up. I could see one access point serving an entire sub-division of gas/water/electric meters, with the AP on a light or utility pole.

I'm using LoRa in point-to-point and broadcast base-to-remotes rather than embracing LoRaWAN. It is one of the better sub-GHz radios I've worked with.

LoRaWAN uses AES which is pulled in as a software library, you could use that to crypt packets. Basic app uses about 15% of FLASH in this micro. Readily ported to L4 with significantly more horse-power and resources.

The US 900 MHz band is 902-928, centred at 915 MHz

[Tesla DeLorean]

Posted on September 12, 2017 at 22:25

LRWAN successfully ported to assorted STM32F4 boards using the SX1272 shield

NUCLEO-F401RE (64)

NUCLEO-F429ZI (144)

NUCLEO-F446ZE (144)

MDOT-915 (Multi-tech F411RET6 based SX1272 design)

https://www.digikey.com/en/product-highlight/m/multi-tech-systems/mdot-series-modules

[Tesla DeLorean]

Posted on September 15, 2017 at 22:28

STM32F412G-DISCOVERY

[Former Member]

Posted on October 03, 2017 at 05:05

Hi Clive

I don't know how to connect to the ST kit B-L072Z-LRWAN1 through USB to my PC. In attached image, i connect to my PC and don'tload usb driver of st-link/v2-1. It don't connect. please show me the image of connecting your PC with target board of the ST kit B-L072Z-LRWAN1.

Thans for your help. David

.

[Tesla DeLorean]

Posted on October 03, 2017 at 23:29

Make sure you have current drivers, they should install as part of the ST-LINK Utilities package, or as the driver only package. You should see 4 or so devices come up related to the ST-LINK, VCP and MSC, etc

Connect directly to the PC, not via a hub. Try another cable, or USB port.

[Tesla DeLorean]

Posted on November 09, 2017 at 22:07

LRWAN successfully ported to STM32F769I-DISC1 board using the SX1272 shield.

PoE powered node.

[Tesla DeLorean]

Posted on December 01, 2017 at 21:14

LRWAN ported to the STM32L4R9I-DISCO (L4+)

board using the SX1272 shield.

[SARTHAK KELAPURE]

Posted on December 19, 2017 at 15:19

Hello Clive,

I need quite some help with this board. I am needing three USARTS and only two available where LPUART is also taken up by vcom. I found PA0 pin which is TX but no RX available for that. Any help on this?

[Andrew Neil]

Posted on December 19, 2017 at 16:18

Answered here:

https://community.st.com/0D50X00009XkX25SAF

[julienterrier39]

Posted on December 20, 2017 at 12:09

Hello everybody,

first of all well done clive for this topic, great initiative. We did a LoRaWan network with the same end-node (i.e

B-L072Z-LRWAN1) type CLASS-A. Then we used a multitech gateway (Conduit-AEP), Senet as 'network server' and Cayenne (mydevices) as 'Application server'.

This architecture will be used only during prototype period...

According to you, is it a good idea to bring back my experience about our LPWAN on this topic?

We have only start for 3 months, for example placement of the gateway has not been optimized despite this with our demonstrator (Minimum Viable Product) 'The-Proof-Of-LoRaWan-Concept' was succes.

[Tesla DeLorean]

Posted on December 20, 2017 at 17:12

You might want to blog post your own experiences.

[richard239955_stm1]

Posted on February 21, 2018 at 03:47

I require some guidance here folks.

My partner and I purchased a 915 MHz LoRaGo Port, mated it to a Raspberry Pi 3 and installed the Semtech

https://github.com/Lora-net/lora_gateway

and Semtech

https://github.com/Lora-net/packet_forwarder

. We found that the json parser does not parse netsed objects, so we flattened local_conf.json and now our gateway shows up with registered status OK on the North American Semtech server.

We also purchase two B-L072Z-LRWAN1 modules and prooved their operation using the ping pong code.

Now we have moved up to the End_Node code in the STM32CubeExpansion_LRWAN_V1.1.3 source tree.

We are using SW4STM32 as generally, the code compiles and works, but, not so this time.

The demonstration code is set up to run at 868 MHz.

What do we do, or what are we supposed to do to switch and compile for US 915 MHz operation?

I see the USE_SEMTECH_DEFAULT_CHANNEL_LINEUP == 1 in lora.c, and all the frequencies are 868 MHz.

Am I supposed to replace those entries below that linewith 915 MHz equivalents, and what would those frequencies be? US region is 64 channels and EU region is 8 channels.

If some kind soul would put me on the right track here, I would really appreciate it.

[SARTHAK KELAPURE]

Posted on February 21, 2018 at 03:57

The way to switch to US915is pretty simple,

1)Right click on the project folder in Project explorer tab.

2) Go to Properties-> C/C++ General-> Paths and Symbols-> Symbols

3) Delete 'REGION_EU868' to 'REGION_US915', but I would recommend you to use 'REGION_US915_HYBRID'

You are ready to go.

NOTE:You shouldn't really make changes to the stack, as you suggested.

[richard239955_stm1]

Posted on February 21, 2018 at 16:26

Thank you for the guidance, will do that shortly and hopefully meet with success.

[algis]

Posted on March 26, 2018 at 12:54

Hello Clive,

I am testing this B-L072Z with STM32CubeExpansion_LRWAN_V1.1.4 and I want to check the bandwidth for tests. However if I turn on the continuous wave mode I get very narrow signal with the BW of ~10kHz (way smaller than 0BW - 125kHz). Can you help with this? It is very frustrating as if I send some packets they seem to cover bigger BW I would say close to 125kHz, but in CW mode it changes. I saw that there are LowDatarateOptimize options, but eve if I set to 0x00 the device do not work properly.

[richard239955_stm1]

Posted on March 26, 2018 at 15:05

Hello Krupta,

As my RF knowledge is mid 70's vintage, my ability to directly respond to your question is very poor.

That being said, have you got a copy of LoRaWAN-Regional-Parameters-v1.1rA.PDF?

If not, go to the LoRa Alliance webpage, get the contact information and submit a request for the LoRa specifications.

If you go through the issues, both open and closed, at this location,

https://github.com/Lora-net/LoRaMac-node

, I suspect that you're going to come close to an answer. The LRWAN Cube code is based on this Semtech code, and you're question pertains more to the radio operation that it does to the resources provided by STM. The Semtech website also has a Community Forum which helped us out with some questions.

Cheers, rtt