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EXTERN Running
EXPORT OSCtxsw
OS_CPO_SR_SAVE
MRS R0,PRIMASK
CPSID 1
BX LR
OS_CPU_SR_Restore
MSR PRIMASK,R0
OSStarthighrdy
LDR R0,=NVIC_STSPRI14
LDR R1,=NVIC_PENDSV_PRI
STRB R1,[R0]
MOVS R0,#0
MOSR PSP,R0
LDR R0,=OSRunning
MOVS R1,#1
STRB R1,[R0]

OSStartHang
B OSStartHang;

OSIntCtxSw
OS_PendSV_Handler
CPSID 1;
MRS R0,PSP
CBZ R0,OS_PendSV_Handler_nosowe
SUBS R0,R0,#0X20
STM R0,{R4-R11}
LDR R1,=OSTCBCUR
LDR R1,[R1]
STR R0,[R1]
OS_CPU_PendSVHandler_nosowe
PUSH {R14}
LDR R0=OSTaskswHook
BLX R0
POP {R14}
LDR R0,=OSPrioCur
LDR R1=OSPrioHighRdy
LDRB R2,[R1]
STRB R2,[R0]

LDR R0,=OSTCBCUR
LDR R1,=OSTCBHighRdy
LDR R2,[R1]
STR R2,[R1]
STR R2,[R0]
LDR R0,[R12]
LDR R0,{R4-R11}
ADDS R0,R0,#0X20
MSR PSP,R0