NAND01G-A STMICROELECTRONICS [STMicroelectronics], NAND01G-A Datasheet - Page 20

• Manufacturer Part Number: NAND01G-A
• Description: 128 Mbit, 256 Mbit, 512 Mbit, 1 Gbit (x8/x16) 528 Byte/264 Word Page, 1.8V/3V, NAND Flash Memories
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

NAND128-A, NAND256-A, NAND512-A, NAND01G-A
DEVICE OPERATIONS
Pointer Operations
As the NAND Flash memories contain two differ-
ent areas for x16 devices and three different areas
for x8 devices (see
codes (00h, 01h, 50h) are used to act as pointers
to the different areas of the memory array (they se-
lect the most significant column address).
The Read A and Read B commands act as point-
ers to the main memory area. Their use depends
on the bus width of the device.
Figure 11. Pointer Operations
20/57
In x16 devices the Read A command (00h)
sets the pointer to Area A (the whole of the
main area) that is Words 0 to 255.
In x8 devices the Read A command (00h) sets
the pointer to Area A (the first half of the main
area) that is Bytes 0 to 255, and the Read B
command (01h) sets the pointer to Area B (the
Bytes 0- 255
Area A
(00h)
A
Figure
(00h,01h,50h)
x8 Devices
Bytes 256-511 Bytes 512
Pointer
Area B
(01h)
11.) the read command
B
Area C
(50h)
-527
C
Page Buffer
In both the x8 and x16 devices the Read C com-
mand (50h), acts as a pointer to Area C (the spare
memory area) that is Bytes 512 to 527 or Words
256 to 263.
Once the Read A and Read C commands have
been issued the pointer remains in the respective
areas until another pointer code is issued. Howev-
er, the Read B command is effective for only one
operation, once an operation has been executed
in Area B the pointer returns automatically to Area
A.
The pointer operations can also be used before a
program operation, that is the appropriate code
(00h, 01h or 50h) can be issued before the pro-
gram command 80h is issued (see
second half of the main area) that is Bytes 256
to 511.
Words 0- 255
x16 Devices
Area A
(00h)
A
(00h,50h)
Pointer
Words 256
Area C
(50h)
-263
C
Figure
Page Buffer
AI07592
12.).