EN25S20A Datasheet, PDF (35/65 Pages) Eon Silicon Solution Inc. – 2 Megabit 1.8V Serial Flash Memory with 4Kbyte Uniform Sector

EN25S20A
Write Suspend (B0h)
Write Suspend allows the interruption of Sector Erase, Half Block Erase, Block Erase or Page Program
operations in order to erase, program, or read data in another portion of memory. The original operation
can be continued with Write Resume command. The instruction sequence is shown in Figure 23.
Only one write operation can be suspended at a time; if an operation is already suspended, the device
will ignore the Write Suspend command. Write Suspend during Chip Erase is ignored; Chip Erase is
not a valid command while a write is suspended.
Suspend to suspend ready timing: 20us.
Resume to another suspend timing: 1ms.
Figure 23. Write Suspend Instruction Sequence Diagram
Write Suspend During Sector Erase or Block Erase
Issuing a Write Suspend instruction during Sector Erase, Half Block Erase or Block Erase allows the
host to program or read any sector that was not being erased. The device will ignore any programming
commands pointing to the suspended sector(s). Any attempt to read from the suspended sector(s) will
out put unknown data because the Sector or Block Erase will be incomplete.
To execute a Write Suspend operation, the host drives CS# low, sends the Write Suspend command
cycle (B0h), then drives CS# high. A cycle is two nibbles long, most significant nibble first. The
Suspend Status register indicates that the erase has been suspended by changing the WSE bit from
“0” to “1”, but the device will not accept another command until it is ready. To determine when the
device will accept a new command, poll the WIP bit in the Suspend Status register or after issue
program suspend command, latency time 20us is needed before issue another command. For
“Suspend to Read”, “Resume to Read”, “Resume to Suspend” timing specification please note Figure
24.1, 24.2 and 24.3.
Write Suspend During Page Programming
Issuing a Write Suspend instruction during Page Programming allows the host to erase or read any
sector that is not being programmed. Erase commands pointing to the suspended sector(s) will be
ignored. Any attempt to read from the suspended page will output unknown data because the program
will be incomplete.
To execute a Write Suspend operation, the host drives CS# low, sends the Write Suspend command
cycle (B0h), then drives CS# high. A cycle is two nibbles long, most significant nibble first. The
Suspend Status register indicates that the programming has been suspended by changing the WSP bit
from “0” to “1”, but the device will not accept another command until it is ready. To determine when the
device will accept a new command, poll the WIP bit in the Suspend Status register or wait after issue
program suspend command, latency time 20us is needed before issue another command. For
“Suspend to Read”, “Resume to Read”, “Resume to Suspend” timing specification please note Figure
24.1, 24.2 and 24.3.
This Data Sheet may be revised by subsequent versions
35
or modifications due to changes in technical specifications.
©2014 Eon Silicon Solution, Inc.,
Rev. A, Issue Date: 2014/01/16
www.eonssi.com