29PL256N datasheet(25/74 Pages) SPANSION

25 / 74 page

June 6, 2007 S29PL-N_00_A5

S29PL-N MirrorBit

™ Flash Family

Da ta

Shee t

(Prelim i nar y )

7.4

Program/Erase Operations

These devices are capable of single word or write buffer programming operations which are described in the

following sections. The write buffer programming is recommended over single word programming as it has

clear benefits from greater programming efficiency. See Table 7.1 on page 20 for the correct device settings

required before initiation of a write command sequence.

Note the following details regarding the program/erase operations:

When the Embedded Program algorithm is complete, the device then returns to the read mode.

The system can determine the status of the program operation by using DQ7 or DQ6. See Write Operation

Status on page 37 for information on these status bits.

A 0 cannot be programmed back to a 1. Attempting to do so causes the device to set DQ5 = 1 (halting any

further operation and requiring a reset command). A succeeding read shows that the data is still 0.

Only erase operations can convert a 0 to a 1.

A hardware reset immediately terminates the program operation and the program command sequence

should be reinitiated once the device has returned to the read mode, to ensure data integrity.

Any commands written to the device during the Embedded Program Algorithm are ignored except the

Program Suspend command.

Secured Silicon Sector, Autoselect, and CFI functions are unavailable when a program operation is in

progress.

Programming is allowed in any sequence and across sector boundaries for single word programming

operation.

7.4.1

Single Word Programming

In single word programming mode, four Flash command write cycles are used to program an individual Flash

address. While this method is supported by all Spansion devices, in general it is not recommended for

devices that support Write Buffer Programming. See Table 12.1 on page 66 for the required bus cycles and

Figure 7.1 on page 26 for the flowchart.

When the Embedded Program algorithm is complete, the device then returns to the read mode and

addresses are no longer latched. The system can determine the status of the program operation by using

DQ7 or DQ6. See Write Operation Status on page 37 for information on these status bits.

Single word programming is supported for backward compatibility with existing Flash driver software and use

of write buffer programming is strongly recommended for general programming. The effective word

programming time using write buffer programming is approximately four times faster than the single word

programming time.

29PL256N Datasheet(PDF) 25 Page - SPANSION