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The Node Layer (centre) in our Driver handles the networking operations for our BL602 LoRaWAN Node ... It's called by the Application Layer (left)

github.com/lupyuen/bl_iot_sdk/

What's MCPS in the Driver? ... That's the "MAC Common Part Sublayer", which is defined in the Semtech LoRaWAN Stack

stackforce.github.io/LoRaMac-d

Semtech Stack is structured according to IEEE 802.15.4 ... Yep LoRaWAN shares the same legacy as Thread, Zigbee and 6LoWPAN! We shall port this Legacy to

en.wikipedia.org/wiki/IEEE_802

The Medium Access Control Layer (right) of our Driver implements the LoRaWAN Protocol: Encryption, Receive Window, Duty Cycle, ... It exposes the MCPS Messaging Interface (IEEE 802.15.4) to the Node Layer (centre) via an Event Queue

github.com/lupyuen/bl_iot_sdk/

The Protocol is explained in this thread: Encryption, Receive Window, Duty Cycle, ...

qoto.org/@lupyuen/105874847933

Curiously, our Driver includes a Command-Line Interface (bottom) that Transmits and Receives LoRa Packets ... Directly calling the SX1276 Driver 🤔

github.com/lupyuen/bl_iot_sdk/

What's an Mbuf? Why is it used by our Driver? Mbufs are Chains of Fixed-Size Blocks ... Works great with little RAM (no fragmentation) ... Created for BSD Unix in 1983!

mynewt.apache.org/latest/os/co

...Which explains why so many folks at STMicro are now reading this Thread

😉

Yep "pbuf" from the Lightweight IP Stack can be used instead of Mbuf ... We just need to shift the Header / Payload Pointer to work on Packets

github.com/lupyuen/bl_iot_sdk/

Reference Implementation of Semtech Stack is here ... Includes drivers for SX1262 and SX1276

github.com/Lora-net/LoRaMac-no

Bought the RAKwireless Gateway: Developer D4H ... Will benchmark this with LoRa Gateway (Also based on RAKwireless RAK2287)

docs.rakwireless.com/Product-C

on RAKwireless can generate random Application Keys for Over-The-Air Activation (OTAA) ... We shall use keys to activate our and devices wirelessly

thethingsindustries.com/docs/d

Something (or Someone) is transmitting Packets every minute ... Signal Strength (RSSI) shows that they're a few hundred metres away

gist.github.com/lupyuen/8dacf0

Based on earlier Coverage Testing (with and ) ... High chance that our Mystery Transmitter is at the nearby Subway Station 🤔

lupyuen.github.io/articles/wis

Someday I might walk around with RAKwireless to find the Mystery Transmitter ... But for now let's test WisGate with WisBlock and BL602!

docs.rakwireless.com/Product-C

Follow

After transmitting a packet, a Device () will open a short "Receive Window" ... To receive a Response Packet (if any) from the LoRaWAN Gateway ()

github.com/lupyuen/wisblock-lo

When hunts for the next Frequency Channel to transmit (Spread Spectrum) ... It listens to the airwaves to check whether the channel is in use ... Let's find out whether BL602 is doing Carrier Sensing correctly 🤔

github.com/lupyuen/bl_iot_sdk/

Oops Mynewt's Carrier Sensing implementation is outdated ... Semtech's LoRaWAN Reference Implementation does NOT require Carrier Sensing outside Japan and South Korea ... So we disable Carrier Sensing and use a random LoRa Frequency Channel

github.com/lupyuen/bl_iot_sdk/

After disabling Carrier Sensing ... hits an Exception while transmitting the Join Network Request ... Let's lookup these addresses in the RISC-V Disassembly

github.com/lupyuen/bl_iot_sdk/

According to our RISC-V Disassembly, Driver hits a Null Pointer Exception here ... Seems like non-essential logging code ... So let's disable this code

github.com/lupyuen/bl_iot_sdk/

is now transmitting the Join Network Request ... But doesn't receive any response from our LoRaWAN Gateway (WisGate) ... Let's check the WisGate LoRaWAN Log

github.com/lupyuen/bl_iot_sdk/

Sadly our Gateway didn't receive any LoRaWAN Packets transmitted by ... Let's look inside the transmitted packets ... And verify the transmission with Airspy SDR

github.com/lupyuen/bl_iot_sdk/

Here's the "Join Network" Chirp ... Recorded by Airspy SDR with CubicSDR

youtu.be/7a4rfaI_zV4

"Join Network" Packet transmitted by ... Looks similar to the one transmitted by BL602 ... Nonce and Message Integrity Code will differ of course

github.com/lupyuen/wisblock-lo

Here are the Packets transmitted by RAKwireless ... Captured by Airspy SDR and CubicSDR

youtu.be/xdyi6XCo8Z8

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@lupyuen
You rock Prof. If You needed adopting clang or fixing that 1bytedma transfers i got some spare resources.

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