FM25Q64ꢀ
ꢀ
11.2.29ꢀReadꢀSecurityꢀRegisterꢀ(2Bh)ꢀ
TheꢀReadꢀSecurityꢀRegisterꢀinstructionꢀisꢀforꢀreadingꢀtheꢀvalueꢀofꢀSecurityꢀRegisterꢀbits.ꢀTheꢀReadꢀ
SecurityꢀRegisterꢀcanꢀbeꢀreadꢀatꢀanyꢀtimeꢀ(evenꢀinꢀprogram/erase/writeꢀstatusꢀregisterꢀcondition)ꢀ
andꢀcontinuously.ꢀ
ꢀ
TheꢀdefinitionꢀofꢀtheꢀSecurityꢀRegisterꢀbitsꢀisꢀasꢀbelow:ꢀ
ꢀ
SecuredꢀOTPꢀIndicatorꢀbit.ꢀTheꢀSecuredꢀOTPꢀindicatorꢀbitꢀshowsꢀtheꢀchipꢀisꢀlockedꢀbyꢀfactoryꢀ
beforeꢀexꢁfactoryꢀorꢀnot.ꢀWhenꢀitꢀisꢀ“0”,ꢀitꢀindicatesꢀnonꢁfactoryꢀlock,ꢀ“1”ꢀindicatesꢀfactoryꢁlock.ꢀ
ꢀ
LockꢁdownꢀSecuredꢀOTPꢀ(LDSO)ꢀbit.ꢀByꢀwritingꢀWRSCURꢀinstruction,ꢀtheꢀLDSOꢀbitꢀmayꢀbeꢀsetꢀ
toꢀ“1”ꢀforꢀcustomerꢀlockꢁdownꢀpurpose.ꢀHowever,ꢀonceꢀtheꢀbitꢀitꢀsetꢀtoꢀ“1”ꢀ(Lockꢁdown),ꢀtheꢀLDSOꢀ
bitꢀandꢀtheꢀ4KꢁbitꢀSecuredꢀOTPꢀareaꢀcannotꢀbeꢀupdatedꢀanyꢀmore.ꢀWhileꢀitꢀisꢀinꢀ4KꢁbitꢀSecuredꢀ
OTPꢀmode,ꢀarrayꢀaccessꢀisꢀnotꢀallowedꢀtoꢀwrite.ꢀ
ꢀ
ꢀ
/CS
Modeꢀ 3
Modeꢀ 0
6
5
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
0
1
2
3
4
CLK
Instructionꢀ(2Bh)
DI
SecurityꢀRegisterꢀꢀout
SecurityꢀRegisterꢀout
DO
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
7
=MSB
ꢀ
Figureꢀ29.ꢀReadꢀSecurityꢀRegisterꢀinstructionꢀsequenceꢀ
ꢀ
SecurityꢀRegisterꢀDefinitionꢀ
Bit7ꢀ
Bit6ꢀ
Bit5ꢀ
Bit4ꢀ
Bit3ꢀ
Bit2ꢀ
Bit1ꢀ
Bit0ꢀ
ꢀ
xꢀ
ꢀ
xꢀ
ꢀ
xꢀ
ꢀ
xꢀ
ꢀ
xꢀ
ꢀ
xꢀ
LDSOꢀ
Securedꢀ
OTPꢀ
indicatorꢀbitꢀ
0ꢀ=ꢀnonꢀ
factoryꢀlockꢀ
1ꢀ=ꢀfactoryꢀ
lockꢀ
(indicateꢀifꢀ
lockꢁdown)ꢀ
0ꢀ=ꢀnotꢀlockꢁ
downꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
reservedꢀ reservedꢀ reservedꢀ
reservedꢀ
reservedꢀ reservedꢀ
1ꢀ=ꢀlockꢁ
down(cannotꢀ
program/eraseꢀ
OTP)ꢀ
Volatileꢀ
bitꢀ
Volatileꢀ
bitꢀ
Volatileꢀ
bitꢀ
Volatileꢀ ꢀ
bitꢀ
Volatileꢀ
bitꢀ
Volatileꢀ
bitꢀ
Nonꢁꢀ
Volatileꢀbitꢀ
Nonꢁ
Volatileꢀbitꢀ
ꢀ
ꢀ
ꢀ
ꢀ
preliminary(Aug.18.2010)ꢀ ꢀ ꢀ ꢀ
46ꢀ
FIDELIX [ FIDELIX ]
