// UseHandler changes handler in currently used vector table.
func (e Exce) UseHandler(handler func()) {
if int(e) >= len(activeVT) {
panic("exce: vector table is too short")
}
activeVT[e] = VectorFor(handler)
barrier.Sync()
}
func main() {
setup.Performance(0)
periph.AHBClockEnable(periph.GPIOB)
periph.AHBReset(periph.GPIOB)
LED.SetMode(Blue, gpio.Out)
LED.SetMode(Green, gpio.Out)
vt := exce.NewTable(16)
vt[exce.NMI] = exce.VectorFor(defaultHandler)
vt[exce.HardFault] = exce.VectorFor(defaultHandler)
vt[exce.SysTick] = exce.VectorFor(sysTickHandler)
exce.UseTable(vt[:])
_, _, tenms := systick.Calib()
tenms *= 10 // stm32l1 returns value for 1 ms not for 10ms.
systick.SetReload(tenms * 100)
systick.SetFlags(systick.Enable | systick.TickInt)
// Sleep forever.
sleep.EnableSleepOnExit()
barrier.Sync() // not necessary on Cortex-M0,M3,M4
sleep.WFI()
// Execution should never reach there so the green LED
// should never light up.
LED.SetBit(Green)
}
func (ts *taskSched) init() {
var vt []exce.Vector
vtlen := 1 << irtExp()
vtsize := vtlen * int(unsafe.Sizeof(exce.Vector{}))
Heap = allocTop(
unsafe.Pointer(&vt), Heap,
vtlen, unsafe.Sizeof(exce.Vector{}), unsafe.Alignof(exce.Vector{}),
uintptr(vtsize),
)
if Heap == nil {
panicMemory()
}
Heap = allocTop(
unsafe.Pointer(&ts.tasks), Heap,
MaxTasks(), unsafe.Sizeof(taskInfo{}), unsafe.Alignof(taskInfo{}),
unsafe.Alignof(taskInfo{}),
)
if Heap == nil {
panicMemory()
}
// Set taskInfo for initial (current) task.
ts.tasks[0].prio = 255
ts.tasks[0].setState(taskReady)
// Use PSP as stack pointer for thread mode.
cortexm.SetPSP(unsafe.Pointer(cortexm.MSP()))
barrier.Sync()
cortexm.SetCtrl(cortexm.Ctrl() | cortexm.UsePSP)
cortexm.ISB()
// Now MSP is used only by exceptions handlers.
cortexm.SetMSP(unsafe.Pointer(initSP(len(ts.tasks))))
// Setup interrupt table.
// Consider setup at link time using GCC weak functions to support Cortex-M0
// and (in case of Cortex-M3,4) to allow vector load on the ICode bus
// simultaneously with registers stacking on DCode bus.
vt[exce.NMI] = exce.VectorFor(nmiHandler)
vt[exce.HardFault] = exce.VectorFor(hardFaultHandler)
vt[exce.MemFault] = exce.VectorFor(memFaultHandler)
vt[exce.BusFault] = exce.VectorFor(busFaultHandler)
vt[exce.UsageFault] = exce.VectorFor(usageFaultHandler)
vt[exce.SVCall] = exce.VectorFor(svcHandler)
vt[exce.PendSV] = exce.VectorFor(pendSVHandler)
vt[exce.SysTick] = exce.VectorFor(sysTickHandler)
exce.UseTable(vt)
exce.MemFault.Enable()
exce.BusFault.Enable()
exce.UsageFault.Enable()
exce.SVCall.SetPrio(exce.Lowest)
exce.PendSV.SetPrio(exce.Lowest)
sysTickStart()
tasker.forceNext = -1
tasker.run()
}