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

Building a Secure #IoT Device? #LoRaWAN works with a Hardware Secure Element

https://lupyuen.github.io/articles/lorawan3?8#secure-element

Setting the #LoRaWAN Frequency for #NuttX OS

https://lupyuen.github.io/articles/lorawan3?9#lorawan-frequency