RC28F640P33B85 Numonyx, RC28F640P33B85 Datasheet - Page 58

• Manufacturer Part Number: RC28F640P33B85
• Description: Numonyx? Strataflash Embedded Memory
• Manufacturer: Numonyx

11.3.1
11.3.1.1
Note:
11.3.2
Datasheet
58
Word Programming
Word programming operations are initiated by writing the Word Program Setup
command to the device. This is followed by a second write to the device with the
address and data to be programmed. The device outputs Status Register data when
read. See
and within the specified V
During programming, the WSM executes a sequence of internally-timed events that
program the desired data bits at the addressed location, and verifies that the bits are
sufficiently programmed. Programming the flash memory array changes “ones” to
“zeros”. Memory array bits that are zeros can be changed to ones only by erasing the
block.
The Status Register can be examined for programming progress and errors by reading
at any address. The device remains in the Read Status Register state until another
command is written to the device.
Status Register bit SR[7] indicates the programming status while the sequence
executes. Commands that can be issued to the device during programming are
Program Suspend, Read Status Register, Read Device Identifier, CFI Query, and Read
Array (this returns unknown data).
When programming has finished, Status Register bit SR[4] (when set) indicates a
programming failure. If SR[3] is set, the WSM could not perform the word
programming operation because V
the word programming operation attempted to program a locked block, causing the
operation to abort.
Before issuing a new command, the Status Register contents should be examined and
then cleared using the Clear Status Register command. Any valid command can follow,
when word programming has completed.
Factory Word Programming
Factory word programming is similar to word programming in that it uses the same
commands and programming algorithms. However, factory word programming
enhances the programming performance with V
programming times during OEM manufacturing processes. Factory word programming
is not intended for extended use. See
for limitations when V
When V
driven by a logic signal, V
V
“Example VPP Supply Connections” on page 62
configurations.
Buffered Programming
The device features a 32-word buffer to enable optimum programming performance.
For Buffered Programming, data is first written to an on-chip write buffer. Then the
buffer data is programmed into the flash memory array in buffer-size increments. This
can improve system programming performance significantly over non-buffered
programming.
When the Buffered Programming Setup command is issued (see
Command Bus Cycles” on page
the availability of the buffer. SR[7] indicates buffer availability: if set, the buffer is
PP
= V
PPH
PP
Figure 33, “Word Program Flowchart” on page
= V
, the device draws programming current from the V
PPL
, the device draws programming current from the V
PP
= V
PPL
PPL
PPH
must remain above V
min/max values.
.
44), Status Register information is updated and reflects
PP
was outside of its acceptable limits. If SR[1] is set,
Section 5.2, “Operating Conditions” on page 26
Numonyx™ StrataFlash
shows examples of device power supply
PP
PPL
= V
MIN to program the device. When
PPH
69. V
. This can enable faster
PP
PP
®
Section 9.6, “Device
must be above V
Embedded Memory (P33)
supply.
Order Number: 314749-05
CC
supply. If V
Figure 30,
November 2007
PPLK
PP
is
,