
28F6408W30, 28F3204W30, 28F320W30, 28F640W30
24
Preliminary
4.5.1
Clear Status Register
To clear the status register, execute the Clear Status Register command. When the status register is 
cleared, only bits 1, 3, 4, and 5 are cleared. A status register bit is considered set if its value is a one 
(1) and cleared if its value is a zero (0). Since bits 0, 2, 6 and 7 indicated different error conditions 
and/or device states, these bits can only be set and cleared by the WSM and are not cleared when a 
Clear Status Register command is given. The status register should be cleared before implementing 
any program or erase operations. After executing the Clear Status Register command, the device 
returns to read array mode. A device reset also clears the status register.
4.6
Read-While-Write/Erase
1.8 Volt Intel
 Wireless Flash Memory supports a new flash multi-partition architecture. By 
dividing the flash memory into many separate partitions, the device is capable of reading from one 
partition while programing or erasing in another partition; hence the terms, Read-While-Write 
(RWW) and Read-While-Erase (RWE). These features greatly enhance flash data storage 
performance.
To perform a RWW operation, execute the Word Program command to one partition. While this 
operation is being performed by the flash WSM, execute the Read Array command to another 
partition.
To perform a RWE operation, execute the Block Erase command to one partition. While this 
operation is being performed by the flash WSM, execute the Read Array command to another 
partition.
1.8 Volt Intel
Wireless Flash Memory does not support simultaneous program and erase operations. 
Attempting to perform operations such as these will result in a command sequence error. Only one 
partition may be programming or erasing while another is reading.
5.0
Program and Erase Voltages
The 1.8 Volt Intel
 Wireless Flash Memory with 3 Volt I/O and SRAM memory provides in-
system program and erase at V
PP1
. For factory programming, it also includes a low-cost, 
backward-compatible 12 V programming feature. It also includes an Enhanced Factory 
Programming (EFP) feature.
5.1
Factory Program Mode
The standard factory programming mode uses the same commands and algorithm as the Word 
Program mode (40h/10h). When V
PP
 is at V
PP1
, program and erase currents are drawn through the 
V
CC
 pin. Note that if V
PP
 is driven by a logic signal, V
PP1 
must remain above the V
PP1
Min value to 
perform in-system flash modifications. When V
PP
 is connected to a 12 V power supply, the device 
draws program and erase current directly from the V
PP
 pin. This eliminates the need for an external 
switching transistor to control the V
PP
 voltage. 
Figure 9, 
“
Example of V
PP
 Power Supply 
Configurations
 shows examples of flash power supply usage in various configurations.