Cube.AI: Hard fault in ai_platform_network_process() function
Hello,
I want to run my own neural network on a NUCLEO-F722ZE board for classifying audio samples. Since there is an older existing example project by STM (Acoustic Scene Classification) so I kept the whole data structure quite similar to this project, using the same network topology and same input vector size.
I loaded my keras .h5 file into X-CUBE-AI and was able to successfully analyze the model and generate code. After this I followed the instructions in the arcticle "How to perform motion sensing on STM32L4 IoTnode" and implemented two functions identical to the AI_Init() and AI_Run() and the respective variables.
I am able to successfully initialize and create the AI model, with the ai_network_1_create_and_init() function returning 0 and the network handle being not null (my given network name is "network_1") . After this I fill the input array with data and call the AI_Run() function, which then again calls my ai_network_1_run() function, which again calls the ai_platform_network_process(). This is how far I can trace the error back. When I step through the lines of code the point of the call of the ai_platform_network_process() function is always where the hard fault interrupt occures. Behind this everything what happens is a black box to me, which leaves me with no other option but asking for help.
After finding this forum post with the same issue, I tried downgrading from X-CUBE-AI v9.0.0 to v8.1.0 and re-generating the code. This doesn't change anything in the behaviour though. Unfortunately I cannot try the suggested v7.x since I run an ARM based Mac.
To me it's really quite odd, since I assume the model is recognized by Cube.AI correctly, because the analyze + code generation is successful. Also the model itself is - apart from the weight values and the output vector size (5 instead of 3) - identical to the Acoustic Scene Classification example project. CRC is also enabled and the init function is called, this was also one thing frequently pointed out in my research.
I tried feeding random float numbers, but also actual spectrogram data into the function (verified with live expressions) with no success. I always get the hard fault.
Here are my functions for the nn handling derived from the knowledgebase article:
ai_handle network;
ai_u8 activations[AI_NETWORK_1_DATA_ACTIVATIONS_SIZE];
ai_buffer * ai_input;
ai_buffer * ai_output;
int AI_Init() {
ai_error err;
/* Create a local array with the addresses of the activations buffers */
const ai_handle act_addr[] = { activations };
/* Create an instance of the model */
err = ai_network_1_create_and_init(&network, act_addr, NULL);
if (err.type != AI_ERROR_NONE) {
printf("ai_network_create error - type=%d code=%d\r\n", err.type, err.code);
return -1;
}
ai_input = ai_network_1_inputs_get(network, NULL);
ai_output = ai_network_1_outputs_get(network, NULL);
return 0;
}
int AI_Run(float* spectrogram, float* classification_result) {
ai_i32 batch;
ai_error err;
/* Update IO handlers with the data payload */
ai_input[0].data = AI_HANDLE_PTR(spectrogram);
ai_output[0].data = AI_HANDLE_PTR(classification_result);
if(network == AI_HANDLE_NULL)
{
printf("E: network handle is NULL\r\n");
return -1;
}
// Run the network
batch = ai_network_1_run(network, ai_input, ai_output);
if (batch != 1) {
err = ai_network_1_get_error(network);
printf("AI ai_network_run error - type=%d code=%d\r\n", err.type, err.code);
return -1;
}
return 0; // Success
}
And here is my main.c:
/* USER CODE BEGIN PV */
float spectrogram[AI_NETWORK_1_IN_1_SIZE];
float aiOutData[AI_NETWORK_1_OUT_1_SIZE];
/* USER CODE END PV */
int main(void)
/* USER CODE BEGIN 1 */
/* USER CODE END 1 */
/* Enable the CPU Cache */
/* Enable I-Cache---------------------------------------------------------*/
SCB_EnableICache();
/* Enable D-Cache---------------------------------------------------------*/
SCB_EnableDCache();
/* MCU Configuration--------------------------------------------------------*/
/* Reset of all peripherals, Initializes the Flash interface and the Systick. */
HAL_Init();
/* USER CODE BEGIN Init */
/* USER CODE END Init */
/* Configure the system clock */
SystemClock_Config();
/* USER CODE BEGIN SysInit */
/* USER CODE END SysInit */
/* Initialize all configured peripherals */
MX_GPIO_Init();
MX_USART3_UART_Init();
MX_USB_OTG_FS_PCD_Init();
MX_CRC_Init();
/* USER CODE BEGIN 2 */
__HAL_RCC_CRC_CLK_ENABLE();
if (AI_Init() != 0) {
printf("Failed to initialize neural network\n");
return -1;
}
for (uint32_t i = 0; i < AI_NETWORK_1_IN_1_SIZE; i++) {
spectrogram[i] = (i+1) / 1.1f; // fill array with example data
}
if (AI_Run(spectrogram, aiOutData) == 0) {
for (uint32_t i = 0; i < AI_NETWORK_1_OUT_1_SIZE; i++) {
printf("%8.6f ", aiOutData[i]);
}
}
/* USER CODE END 2 */
/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
I also attached my model.h5 file. Any help getting this to work is very much appreciated.
Thanks,
Leon