Problem with invalid read/write with STM32F7 FMC NAND Flash memory
Hi,
I am working with a custom board using the STM32F765VGT6 which is connected to a NAND flash chip, the WN29N02GV, via the FMC peripheral.
I have been able to read the flash ID correctly, but am having issues with the reading and writing data.
I wrote a simple program, to write data to a page, and then read back the data and compare. The problem is that the data read in, does not match the data that was written. The program is shown below:
void vTestMemory(void * pvParams){
//Write Protect Pin should be high.
HAL_GPIO_WritePin(FLASH_WP_GPIO_Port, FLASH_WP_Pin, 1);
HAL_NAND_Reset(&hnand1);
NAND_IDTypeDef nandInfo;
//For reference, the W29N02GV id:
// nandInfo.Device_Id = 0xDA;
// nandInfo.Maker_Id = 0xEF;
// nandInfo.Third_Id=90;
// nandInfo.Fourth_Id =95;
NAND_AddressTypeDef addr;
addr.Block = 0;
addr.Page = 0;
addr.Plane = 0;
HAL_NAND_Erase_Block(&hnand1, &addr);
HAL_StatusTypeDef res = HAL_NAND_Read_ID(&hnand1,&nandInfo);
uint8_t testBuff [hnand1.Config.PageSize];
uint8_t testBuffRx [hnand1.Config.PageSize];
while(1){
for(int i=0; i< hnand1.Config.PageSize; i++){
testBuff[i] = i%256;
testBuffRx[i]= 0 ;
}
HAL_NAND_Read_Page_8b(&hnand1, &addr, testBuffRx, 1);
HAL_NAND_Write_Page_8b(&hnand1, &addr, testBuff, 1);
HAL_NAND_Read_Page_8b(&hnand1, &addr, testBuffRx, 1);
uint16_t good = 0;
for(int i=0; i<hnand1.Config.PageSize; i++){
if(testBuffRx[i] != testBuff[i]){
good ++;
}
}
HAL_NAND_Address_Inc(&hnand1, &addr);
if(addr.Block == 2048 && addr.Page == 64){
uint8_t a = 0;//End of memory, breakpoint here...
}
vTaskDelay(pdMS_TO_TICKS(5));
}
}Specifically, the data that is read in should be a repeating sequence of bytes counting from 0 to 255, but the actual data read in seems to miss the last bytes, and at some point(s) in the page, it looks like a value is skipped, or a byte was missed. The point at which the first error appears changes and doesn't appear to have a pattern.
I'm not sure whether the issue is with the read or the write, and the issue is consistenly happening, after the first time I ran the code, when it seemed to work fine.
Does anyone have any suggestions for what the error might be or any solution for getting valid data ?
I have setup the flash memory using STM32CubeMX, and the following initialization function was generated:
void MX_FMC_Init(void)
{
/* USER CODE BEGIN FMC_Init 0 */
/* USER CODE END FMC_Init 0 */
FMC_NAND_PCC_TimingTypeDef ComSpaceTiming = {0};
FMC_NAND_PCC_TimingTypeDef AttSpaceTiming = {0};
/* USER CODE BEGIN FMC_Init 1 */
/* USER CODE END FMC_Init 1 */
/** Perform the NAND1 memory initialization sequence
*/
hnand1.Instance = FMC_NAND_DEVICE;
/* hnand1.Init */
hnand1.Init.NandBank = FMC_NAND_BANK3;
hnand1.Init.Waitfeature = FMC_NAND_WAIT_FEATURE_ENABLE;
hnand1.Init.MemoryDataWidth = FMC_NAND_MEM_BUS_WIDTH_8;
hnand1.Init.EccComputation = FMC_NAND_ECC_ENABLE;
hnand1.Init.ECCPageSize = FMC_NAND_ECC_PAGE_SIZE_2048BYTE;
hnand1.Init.TCLRSetupTime = 0;
hnand1.Init.TARSetupTime = 0;
/* hnand1.Config */
hnand1.Config.PageSize = 2048;
hnand1.Config.SpareAreaSize = 64;
hnand1.Config.BlockSize = 64;
hnand1.Config.BlockNbr = 2048;
hnand1.Config.PlaneNbr = 2;
hnand1.Config.PlaneSize = 1024;
hnand1.Config.ExtraCommandEnable = DISABLE;
/* ComSpaceTiming */
ComSpaceTiming.SetupTime = 40;
ComSpaceTiming.WaitSetupTime = 120;
ComSpaceTiming.HoldSetupTime = 120;
ComSpaceTiming.HiZSetupTime = 40;
/* AttSpaceTiming */
AttSpaceTiming.SetupTime = 40;
AttSpaceTiming.WaitSetupTime = 120;
AttSpaceTiming.HoldSetupTime = 120;
AttSpaceTiming.HiZSetupTime = 40;
if (HAL_NAND_Init(&hnand1, &ComSpaceTiming, &AttSpaceTiming) != HAL_OK)
{
Error_Handler( );
}
/* USER CODE BEGIN FMC_Init 2 */
/* USER CODE END FMC_Init 2 */
}I have tried changing the timing parameters, which doesn't fix the issues.
I'm running the memory test as a FreeRTOS task, but I have tried without FreeRTOS and the issue was still happening.
I have the MPU disabled, and all the caching turned off.