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P/N:PM1201 REV. 2.2, DEC. 04, 2012
MX29F040C
REQUIREMENTS FOR READING ARRAY DATA
Readarrayactionistoreadthedatastoredinthearrayout.Whilethememorydeviceisinpowereduporhas
beenreset,itwillautomaticallyenterthestatusofreadarray.Ifthemicroprocessorwantstoreadthedatastored
inarray,ithastodriveCE#(deviceenablecontrolpin)andOE#(Outputcontrolpin)asVil,andinputtheaddress
ofthedatatobereadintoaddresspinatthesametime.Afteraperiodofreadcycle(TceorTaa),thedatabeing
readoutwillbedisplayedonoutputpinformicroprocessortoaccess.IfCE#orOE#isVih,theoutputwillbein
tri-state,andtherewillbenodatadisplayedonoutputpinatall.
Afterthememorydevicecompletesembeddedoperation(automaticEraseorProgram),itwillautomaticallyre-
turntothestatusofreadarray,andthedevicecanreadthedatainanyaddressinthearray.Intheprocessof
erasing,if thedevice receivesthe Erasesuspend command,erase operationwill bestopped aftera periodof
timenomorethanTreadyandthedevicewillreturntothestatusofreadarray.Atthistime,thedevicecanread
thedatastoredinanyaddressexceptthesectorbeingerasedinthearray.Inthestatusoferasesuspend,ifuser
wantstoreadthedatainthesectorsbeingerased,thedevicewilloutputstatusdataontotheoutput.Similarly,if
programcommandisissuedaftererasesuspend,afterprogramoperationiscompleted,systemcanstillreadar-
raydatainanyaddressexceptthesectorstobeerased.
Thedeviceneedstoissueresetcommandtoenablereadarrayoperationagaininordertoarbitrarilyreadthe
datainthearrayinthefollowingtwosituations:
1.Inprogramoreraseoperation,theprogrammingorerasingfailurecausesQ5togohigh.
2.Thedeviceisinautoselectmode.
Inthe twosituationsabove, ifresetcommand isnot issued,thedevice isnot inreadarray modeandsystem
mustissueresetcommandbeforereadingarraydata.
WRITE COMMANDS/COMMAND SEQUENCES
Towriteacommandtothedevice,systemmustdriveWE#andCE#toVil,andOE#toVih.Inacommandcycle,
alladdress arelatchedat thelaterfalling edgeof CE#andWE#, andall dataarelatched attheearlier rising
edgeofCE#andWE#.
"Figure 1. COMMAND WRITE OPERATION"illustratestheACtimingwaveformofawritecommand,and"TA-
BLE 3. MX29F040C COMMAND DEFINITIONS"denesallthevalidcommandsetsofthedevice.Systemisnot
allowedtowriteinvalidcommandsnotdenedinthisdatasheet.Writinganinvalidcommandwillbringthedevice
toanundenedstate.
AUTOMATIC SELECT OPERATION
Whenthedevice isinRead arraymodeor erase-suspended readarray mode, usercanissue readsiliconID
commandtoenterreadsiliconIDmode.AfterenteringreadsiliconIDmode,usercanqueryseveralsiliconIDs
continuouslyanddoes notneedto issuereadsilicon ID modeagain. WhenA0 isLow,device will outputMa-
cronixManufactureIDC2.WhenA0ishigh,devicewilloutputDeviceID.InreadsiliconIDmode,issuingreset
commandwillresetdevicebacktoreadarraymodeorerase-suspendedreadarraymode.
AnotherwaytoenterreadsiliconIDistoapplyhighvoltageonA9pinwithCE#,OE#andA1atVil.Whilethe
highvoltageofA9pinisdischarged,devicewillautomaticallyleavereadsiliconIDmodeandgobacktoread
arraymodeorerase-suspendedreadarraymode.WhenA0isLow,devicewilloutputMacronixManufactureID
C2.WhenA0ishigh,devicewilloutputDeviceID.