#NuttX OS doesn't handle the Join Response from #LoRaWAN Gateway ... Let's fix this

Run Log: https://gist.github.com/lupyuen/a8e834e7b4267345f01b6629fb7f5e33

Our #NuttX App was waiting for the #LoRaWAN Join Request to be transmitted before receiving the Join Response ... But because we're polling SX1262, we missed the Join Response ... Let's fix this with the multithreading functions from NimBLE Porting Layer

Log: https://gist.github.com/lupyuen/d3d9db37a40d7560fc211408db04a81b

NimBLE Porting Layer is a portable library of Multithreading Functions ... We've used it for #LoRa on Linux and FreeRTOS ... Now we call it from Apache #NuttX OS

https://github.com/lupyuen/nimble-porting-nuttx

To build NumBLE Porting Layer on #NuttX OS we need to enable: 1️⃣ POSIX Timers & Message Queues 2️⃣ Clock Monotonic 3️⃣ Work Queues 4️⃣ SIGEV_THHREAD

https://github.com/lupyuen/nimble-porting-nuttx

#LoRaWAN runs neater on Apache #NuttX OS ... After implementing Timers and Multithreading with NimBLE Porting Layer ... No more polling and sleep()!

https://gist.github.com/lupyuen/cad58115be4cabe8a8a49c0e498f1c95

Here's our #LoRaWAN Event Loop for #NuttX OS ... Implemented with NimBLE Porting Library ... No more polling!

https://github.com/lupyuen/incubator-nuttx-apps/blob/lorawan/examples/lorawan_test/lorawan_test_main.c#L814-L857

Here's how we check the SX1262 Busy Pin on #NuttX OS ... By reading the GPIO Input

https://github.com/lupyuen/lora-sx1262/blob/lorawan/src/sx126x-nuttx.c#L184-L199

SX1262 will trigger a GPIO Interrupt on #NuttX OS when it receives a #LoRa Packet ... We wait for the GPIO Interrupt to be Signalled in a Background Thread

https://github.com/lupyuen/lora-sx1262/blob/lorawan/src/sx126x-nuttx.c#L742-L778

We handle GPIO Interrupts (SX1262 DIO1) in a #NuttX Background Thread ... Awaiting the Signal for GPIO Interrupt

https://github.com/lupyuen/lora-sx1262/blob/lorawan/src/sx126x-nuttx.c#L835-L861

Our #NuttX Background Thread handles the GPIO Interrupts (SX1262 DIO1) ... By adding to the #LoRaWAN Event Queue

https://github.com/lupyuen/lora-sx1262/blob/lorawan/src/sx126x-nuttx.c#L863-L892

Our #NuttX App resends the same Nonce to the #LoRaWAN Gateway ... Which (silently) rejects the Join Request due to Duplicate Nonce ... Let's fix our Random Number Generator

https://gist.github.com/lupyuen/b38434c3d27500444382bb4a066691e5

#LoRaWAN gets the Nonce from the Secure Element's Random Number Generator ... Let's simulate the Secure Element on Apache #NuttX OS

https://github.com/lupyuen/LoRaMac-node-nuttx/blob/master/src/mac/LoRaMacCrypto.c#L980-L996

We enable the Entropy Pool in #NuttX OS ... To generate Strong Random Numbers for our #LoRaWAN Nonce

For #NuttX Random Number Generator, select the Entropy Pool ... To generate Strong Random Numbers for our #LoRaWAN Nonce

Here's how we generate #LoRaWAN Nonces on #NuttX OS ... With Strong Random Numbers thanks to Entropy Pool

https://github.com/lupyuen/LoRaMac-node-nuttx/blob/master/src/nuttx.c#L136-L153

Our #NuttX App now sends Random #LoRaWAN Nonces to the LoRaWAN Gateway ... And are happily accepted by the gateway! 🎉

Log: https://gist.github.com/lupyuen/8f012856b9eb6b9a762160afd83df7f8

Our #NuttX App was too busy to receive the #LoRaWAN Join Response ... Let's disable the logging

Log: https://gist.github.com/lupyuen/8f012856b9eb6b9a762160afd83df7f8

After disabling logging, our #NuttX App successfully joins the #LoRaWAN Network! 🎉 Now we transmit some Data Packets over LoRaWAN

Log: https://gist.github.com/lupyuen/0d301216bbf937147778bb57ab0ccf89

Our #LoRaWAN Gateway receives Data Packets from #NuttX OS! 🎉 The Message Payload is empty ... Let's figure out why 🤔

Log: https://gist.github.com/lupyuen/0d301216bbf937147778bb57ab0ccf89

Our #NuttX App sent an empty #LoRaWAN Message because our message is too long for LoRaWAN Data Rate 2 (max 11 bytes) ... Let's increase the Data Rate to 3

https://gist.github.com/lupyuen/5fc07695a6c4bb48b5e4d10eb05ca9bf

Here's how we increase the #LoRaWAN Data Rate to 3 in our #NuttX App

https://github.com/lupyuen/lorawan_test/blob/main/lorawan_test_main.c#L57-L70

#LoRaWAN Data Rate has been increased to 3 ... Max Message Size is now 53 bytes for our #NuttX App

https://gist.github.com/lupyuen/83be5da091273bb39bad6e77cc91b68d

#LoRaWAN Gateway now receives the correct Data Packet from our #NuttX App! 🎉

https://gist.github.com/lupyuen/83be5da091273bb39bad6e77cc91b68d

Here's how we send a #LoRaWAN Data Packet on #NuttX OS ... And validate the Packet Size before sending

https://github.com/lupyuen/lorawan_test/blob/main/lorawan_test_main.c#L311-L339

#LoRaWAN tested OK on Apache #NuttX OS ... From #PineDio Stack BL604 @PINE64 to RAKwireless WisGate ... And back! 🎉

https://github.com/lupyuen/LoRaMac-node-nuttx

NimBLE Porting Layer doesn't work for multiple Callout Timers on #NuttX OS, unless we loop the thread ... Will submit a Pull Request to Apache NimBLE 👍

https://github.com/lupyuen/nimble-porting-nuttx/blob/master/porting/npl/nuttx/src/os_callout.c#L35-L70

Switching a #NuttX GPIO Interrupt Pin to Trigger On Rising Edge ... Crashes with an Assertion Failure ... I'll submit a NuttX Issue, meanwhile I have disabled the assertion

https://github.com/lupyuen/incubator-nuttx/blob/lorawan/drivers/ioexpander/gpio.c#L544-L547

Here's why we need GPIO Interrupts Triggered on Rising Edge for #LoRa on #NuttX

https://lupyuen.github.io/articles/sx1262?88#initialise-gpio

We handle SX1262 GPIO Interrupts in #NuttX with a Background Thread ... That inserts into an Event Queue

https://lupyuen.github.io/articles/sx1262?89#start-dio1-thread

How we handle SX1262 GPIO Interrupts in #NuttX OS ... With NimBLE Porting Layer

https://lupyuen.github.io/articles/sx1262?90#multithreading-with-nimble-porting-layer

We handle #LoRaWAN Events in our #NuttX App ... With this Event Loop

https://lupyuen.github.io/articles/sx1262?91#event-loop

Porting #LoRaWAN to Apache #NuttX OS ... All shall be explained in this article

https://lupyuen.github.io/articles/lorawan3?1

Here's why we ported Semtech's #LoRaWAN Stack to #NuttX OS ... With minimal changes

https://lupyuen.github.io/articles/lorawan3?2#small-steps

Here are the dependencies for #LoRaWAN on #NuttX OS

https://lupyuen.github.io/articles/lorawan3?3#dependencies

#LoRaWAN on #Apache NuttX OS ... Here's what we'll do

https://lupyuen.github.io/articles/lorawan3?4#lorawan-objective

Here's what we'll do with #LoRaWAN on Apache #NuttX OS

https://lupyuen.github.io/articles/lorawan3?5#lorawan-objective

Source Code for #LoRaWAN on Apache #NuttX OS

https://lupyuen.github.io/articles/lorawan3?6#download-source-code

Setting the #LoRaWAN Device EUI and App Key in #NuttX OS

https://lupyuen.github.io/articles/lorawan3?7#device-eui-join-eui-and-app-key