entry.s .global miniOS_irqhandler miniOS_irqhandler: msr cpsr_c, #0xc0 | 0x12// IRQ mode ldr sp, = TCB_PtrCurrentTask ldr sp, [sp] sub lr, lr, #4 add sp, sp, #4 stmia sp!, {r0-r12}^ stmia sp! {sp,lr}^ stmia sp! {lr} sub sp, sp, #68 mrs r1, spsr stmia sp!, {r1} ldr sp, TCB_IRQStack bl irqHandler ldr sp, = TCB_PtrNextTask ldr sp, [sp] ldmia sp!, {r1} msr spsr_cxsf, r1 ldmia sp!, {r0-r12}^ ldmia sp!, {r13, r14}^ ldmia sp!, {pc}^ |