28F008/800B3, 28F016/160B3, 28F320B3, 28F640B3
10.1
Bus Operations
The B3 flash memory device performs read, program, and erase in-system operations through the
local CPU or microcontroller. All bus cycles to or from the flash memory conform to standard
microcontroller bus cycles. Four control pins dictate the data flow in and out of the flash memory
device:
• CE#
• OE#
• WE#
• RP#
Table 27 summarizes these bus operations.
Table 27.
Bus Operations(1)
Mode
Note
RP#
CE#
OE#
WE#
DQ0–7
DQ8–15
Read (Array, Status, or Identifier)
2–4
2
VIH
VIH
VIH
VIL
VIH
VIL
VIL
VIH
X
VIL
VIH
X
VIH
VIH
X
DOUT
High Z
High Z
High Z
DIN
DOUT
High Z
High Z
High Z
DIN
Output Disable
Standby
Reset
2
2, 7
2, 5–7
X
X
Write
VIL
VIH
VIL
Notes:
1.
8-bit devices use only DQ[0:7].
16-bit devices use DQ[0:15].
2.
3.
4.
5.
6.
7.
X must be VIL, VIH for control pins and addresses.
See DC Characteristics for VPPLK, VPP1, VPP2, VPP3, VPP4 voltages.
Manufacturer and device codes can also be accessed in read identifier mode (A1–A21 = 0). See Table 29.
Refer to Table 30 for valid DIN during a Write operation.
To program or erase the lockable blocks, hold WP# at VIH
.
RP# must be at GND 0.2 V to meet the maximum deep power-down current specified.
10.1.1
Read
The B3 flash memory device provides four read modes:
• read array
• read identifier
• read status
• read query
These modes are accessible independently of the V voltage. Issue the appropriate Read Mode
PP
command to the CUI to enter the corresponding mode. Upon initial device power-up or after exit
from reset, the flash memory device automatically defaults to read-array mode.
CE# and OE# must be driven active to obtain data at the outputs.
• CE# is the device selection control. When active, CE# enables the flash memory device.
• OE# is the data output control, and drives the selected memory data onto the I/O bus.
For all read modes, WE# and RP# must be at V . Figure 10 on page 40 illustrates a read cycle.
IH
Datasheet
Intel® Advanced Boot Block Flash Memory (B3)
Order Number: 290580, Revision: 020
18 Aug 2005
51
NUMONYX [ NUMONYX B.V ]
