Our #BL602 Build, Flash and Run Firmware script generates the #RISCV Disassembly ... Let's track down the address of the RISC-V Exception
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/run.sh
Oops the Program Counter for our #RISCV Exception is null ... So there must be a missing Callback Function somewhere in our #LoRa #BL602 Firmware 🤔
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/sdk_app_lora/demo.c
#BL602 #LoRa Exception happened because we passed a pointer to a stack object ... Which gets used by the Interrupt Handler 😲 ... This works OK in the original Mynewt code, but not for BL602
https://gist.github.com/lupyuen/1539f9dd52e9a83d4fbe7724481112bf
For #BL602 we fix this exception by copying the object ... Instead of storing a pointer to the object
#BL602 now displays the #LoRa Packet received from #WisBlock yay!
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/sdk_app_lora/demo.c
Mystery #BL602 GPIO Function ... What does it do? Will it fix our problem with triggering multiple GPIO Interrupts? 🤔
#BL602 Reference Manual mentions "GPIO_INT_CLR" but the address is undefined in the doc ... Methinks a chunk of addresses are missing from the doc 🤔
https://github.com/bouffalolab/bl_docs/tree/main/BL602_RM/en
Searching GitHub for "GPIO_INT_CLR" shows ultraembedded RISC-V SoC ... Coincidence? 🤔
https://github.com/search?l=Markdown&q=GPIO_INT_CLR&type=Code
Ah my folly ways ... Multiple #BL602 GPIO Interrupts can't be registered like this ... Lemme fix this 🪠
Let's handle #BL602 GPIO Interrupts the smarter way ... By iterating thru the Interrupt Events created with the NimBLE Porting Layer
Reconnected #PineCone #BL602 @PINE64 ... To #LoRa SX1276 pins DIO0 to DIO3 ... For testing our GPIO interrupt handler
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/sdk_app_lora/sx1276.h
Enabled #BL602 GPIO Interrupt Handler for #LoRa SX1276 ... And BL602 hits a #RISCV Exception ... At an invalid Program Address 🤔
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/sdk_app_lora/demo.c
Let's disable #LoRa Channel Activity Detection for now ... #BL602 receives first LoRa Packet ... But not the second packet 🤔
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/sdk_app_lora/demo.c
Can #BL602 show the Stack Trace for this #RISCV Exception? ... Let's find out 🤔
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/sdk_app_lora/demo.c
#BL602 shows Stack Trace when CONFIG_ENABLE_FP=1 ... But the addresses don't make sense ... They belong to the code that's dumping the Stack Trace 🤔
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/proj_config.mk#L40-L42
Let's dump the #BL602 Stack with this function ... And figure out why our Exception Stack Trace doesn't look right
Here are the #BL602 Stacks for the Foreground RTOS Task, Background Task and Exception Handler ... Let's see what's wrong with the Exception Stack
Complete #BL602 Stack Data for the Exception is here
https://gist.github.com/lupyuen/5ddbcdd1054c775521291c3d114f6cee
Below the #BL602 Exception Handler Stack ... Is another Stack! ... Does this Stack contain the Stack Trace that we need? 🤔
https://gist.github.com/lupyuen/5ddbcdd1054c775521291c3d114f6cee
Quiz: What's wrong with this C code? 🤔 ... I'm soooo upset I missed this simple bug 🙄
https://github.com/apache/mynewt-core/blob/master/apps/loraping/src/main.c#L215-L233
Answer: "radio_events" contains Undefined Fields ... Because it was allocated on the Stack! Lesson Learnt: ALWAYS Init Stack Variables! 🙏
https://github.com/apache/mynewt-core/blob/master/apps/loraping/src/main.c#L215-L233
Back to our #BL602 Stack Trace ... Yep the Correct Stack Trace is indeed lurking behind our (unhelpful) Exception Stack Trace ... How shall we show the Correct Stack Trace beyond the Emptiness? 🤔
https://gist.github.com/lupyuen/5ddbcdd1054c775521291c3d114f6cee
Let's do #BL602 #LoRa Receive Timeout with these Callout Functions from the NimBLE Porting Layer
https://lupyuen.github.io/pinetime-rust-mynewt/articles/dfu#nimble-callout-functions
#BL602 receives 4 #LoRa Packets by executing 458 SPI requests ... Great load test for SPI 👍
https://github.com/lupyuen/bl_iot_sdk/blob/lorarecv/customer_app/sdk_app_lora/sdk_app_lora/demo.c
#PineCone #BL602 @PINE64 receiving #LoRa Packets from RAKwireless #WisBlock ... All shall be explained in this article. Thanks for reading this looong thread 🙏
https://lupyuen.github.io/articles/lora2