UM1653 datasheet(13/45 Pages) STMICROELECTRONICS

13 / 45 page

DocID025024 Rev 1

13/45

UM1653

NAND driver firmware modules

Figure 5. Flow of wear leveling mechanism for STEVAL-CCM007V1/ 008V1

The above figure gives an overview of the firmware flow with respect to the way the Wear

Leveling Mechanism is implemented.

Let us consider a scenario in which the host is trying to send the data to the controller via

USB and write it to the NAND Flash. The corresponding CBW has to be decoded. The

function given below is called in such a case, to write to the memory which uses the

information provided from the CBW

void SCSI_Write10_Cmd(uint8_t lun, uint32_t LBA, uint32_t BlockNbr)

This function has the following arguments, the logical unit number, Logical block address

(LBA) and the block number. The LBA passed from the host is sequential and maps to the

address of the block in NAND Flash memory which comes out to be sequential.

A structure is used to store the address:

typedef struct

{

uint16_t Zone;

uint16_t Block;

uint16_t Page;

} NAND_ADDRESS;

main

NAND_Init

NAND_CleanLUT

NAND_WearLeveling

SBLK_NAND_WearLeveling

LBLK_NAND_WearLeveling

Small Block

NAND?

OTG_FS_IRQHandler

USBD_OTG_ISR_Handler

DCD_HandleOutEP_ISR

USBD_DataOutStage

USBD_MSC_DataOut

Is another Zone

requested?

Write in current Zone

of NAND Flash

Yes

SCSI_ProcessCmd

SCSI_Write10

SCSI_ProcessWrite

STORAGE_Write

NAND_Write

MSC_BOT_Data_Out

MS33219V1

UM1653 Datasheet(PDF) 13 Page - STMicroelectronics

UM1653 Datasheet(HTML) 13 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45

Datasheet Descarga

Enlace URL