nand.PageRead

#include <file_config.h>

U32 PageRead  (
    U32           row,        /* Page address           */
    U8*           buf,        /* Pointer to data buffer */
    NAND_DRV_CFG* cfg);       /* Device configuration   */

The function ReadPage reads data from a NAND Flash device. The parameter row specifies the address of the starting page. The parameter buf is a pointer to the buffer that receives the data. The parameter cfg is a pointer specifying the device configuration, which also contains default data positions as described in Page Layout Structure.

The function is part of the NAND Driver. The prototype is defined in the file File_Config.h. Developers must customize the function.

• RTV_NOERR - on success.
• ERR_NAND_HW_TOUT - Hardware data transfer timeout.
• ERR_ECC_COR - ECC corrected the errors. The transmitted data are valid.
• ERR_ECC_UNCOR - ECC could not correct an error. The transmitted data contain errors.

nand.BlockErase, nand.Init, nand.PageWrite, nand.UnInit

/* NAND Device Driver Control Block */
NAND_DRV nand0_drv = {
  Init,
  UnInit,
  PageRead,
  PageWrite,
  BlockErase
};

static U32 PageRead (U32 row, U8 *buf, NAND_DRV_CFG *cfg) {
  U32 i, sec, ecc;
  U32 *p = (U32 *)buf;

  MLC_CMD = NAND_CMD_READ1ST;               /* Read command (1st cycle) */
  if (cfg->PageSize > 528) {
    MLC_CMD = NAND_CMD_READ2ND;             /* Read command (2nd cycle) */
  }
  SetAddr (row << 8, cfg->AddrCycles);      /* Set address */

  ecc = ECC_NOERR;

  for (sec = 0; sec < cfg->SectorsPerPage; sec++) {
    MLC_ECC_AUTO_DEC_REG = 0x00;            /* Auto Decode */
    if (!StatusFlag (NAND_CON_READY)) {     /* Wait for controller ready */
      return ERR_NAND_HW_TOUT;
    }
    if (!StatusFlag (NAND_ECC_READY)) {     /* Wait for ECC ready */
      return ERR_NAND_HW_TOUT;
    }

    if (MLC_ISR & NAND_ERR_DET) {           /* Check for decode error */
      ecc |= ECC_CORRECTED;
    }
    if (MLC_ISR & NAND_DEC_FAIL) {
      ecc |= ECC_UNCORRECTED;
    }
    for (i = 0; i < (528 >> 2); i++) {
      *p++ = MLC_BUFFX (i);                 /* Read main + spare area */
    }
  }
  if (ecc & ECC_UNCORRECTED) {
    return ERR_ECC_UNCOR;                   /* ECC could not correct the error */
  }
  if (ecc & ECC_CORRECTED) {
    return ERR_ECC_COR;                     /* ECC corrected the data within page */
  }
  return RTV_NOERR;
}