Buffer Layout And Page Mapping For Large-Page Nand Flash Devices - Freescale Semiconductor MPC8313E Family Reference Manual

Enhanced Local Bus Controller
small and large-page devices, a large-page 4-Kbyte buffer must be assigned to either the first 4 or last 4
small-page buffers.
Bank Base Address
offset 0x0400
offset 0x0800
offset 0x0C00
offset 0x1000
offset 0x1400
offset 0x1800
offset 0x1C00
offset 0x2000
End of Bank
Figure 10-46. FCM Buffer RAM Memory Map for Small-Page (512-byte page) NAND Flash Devices
10.4.3.1.2

Buffer Layout and Page Mapping for Large-Page NAND Flash Devices

The FCM buffer space is divided into two 4 Kbyte buffers for large-page devices (ORn[PGS] = 1), mapped
as shown in Figure 10-47. Each page in a large-page NAND Flash comprises 2112 bytes, where 2048 bytes
appear as main region data, and 64 bytes appear as spare region data. The EEPROM's page numbered P
is associated with buffer number (P mod 2), where P = FPAR[PI]. Since the bank size set by ORn[AM]
will be greater than 8 Kbytes, an identical image of the FCM buffer RAM appears replicated every 8
Kbytes throughout the bank address space. It is recommended that the bank size be set to 256 Kbytes,
which covers a single NAND Flash block for large-page devices.
For FCM commands, register FPAR sets the page address and, therefore, also the buffer number. In the
case that FBCR[BC] = 0, FCM transfers an entire page, comprising the 2048-byte main region followed
by the 64-byte spare region; the 1984-byte reserved region is not accessed, and remains undefined for
software. However, for commands given a specific byte count in FBCR[BC], FPAR[MS] locates the
starting address in either the main region (MS = 0) or the spare region (MS = 1). Where different eLBC
MPC8313E PowerQUICC II Pro Integrated Processor Family Reference Manual, Rev. 3
10-62
buffer #0/page 0
buffer #1/page 1
buffer #2/page 2
buffer #3/page 3
buffer #4/page 4
buffer #5/page 5
buffer #6/page 6
buffer #7/page 7
replicated FCM
buffer RAM
images in bank
1 Kbyte page buffer:
512-byte main region (FPAR[MS] = 0)
16-byte spare region (FPAR[MS] = 1)
496-byte reserved region (FPAR[MS] = 1)
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