How do I use the cJSON library?

[June6]

I need to use cJSON to parse the uart data. I found the file in SDK15.3 but how can I use the related function?

[June6]

I think I found the reason. This issue can occur if the total number of blocks from XXS to XXL exceeds 255. This is independent of the block size, and I firmly believe that the size of each memory block I set is reasonable. Because, I use nrf_malloc to apply for the memory of the corresponding block size to determine whether to return null, and observe whether the number of successful applications corresponds to the number I set. The final result is correct. So how can I solve the HardFault_Handler caused by cJSON_CreateNumber?

[Dmitry]

Hi,

It's not clear to me.. you say that you solved the problem with nrf_malloc, and with malloc it doesn't crash. What IDE are you using? Could you show debug trace (disassembly, stack, registers) where hard fault occures?

[June6]

Yes, there is no problem when parsing JSON data. But when I create JSON data, I will use cJSON_CreateNumber. So after I blocked all the other parts related to JSON parsing, I called cJSON_CreateNumber and found that as long as the total number of memory blocks from XXS to XXL exceeds 255, calling cJSON_CreateNumber will cause the program to die in HardFault_Handler. There is no log information (I didn't open men_manger module log)

[June6]

Whether to use malloc is not the key, the key is that when I call nrf_mem_init, and the total number of memory blocks from XXS to XXL exceeds 255, calling cJSON_CreateNumber will cause the program to die in HardFault_Handler.

[June6]

The IDE I am using is SES and KEIL, and I don't know how to display debug traces (disassembly, stack, registers) where hard faults occur. The end result is just the program stuck in HardFault_Handler