AN2897 Freescale Semiconductor / Motorola, AN2897 Datasheet - Page 20

• Manufacturer Part Number: AN2897
• Description: Using the eTPU Angle Clock
• Manufacturer: Freescale Semiconductor / Motorola

eTPU Software Design
20
PossibleGapVerifying
GapVerified
Counting
Gapping
Reference
Name
StallTimer = StallPeriod at startpoint Time(activeEdge)
StallTimer = StallPeriod at startpoint Time(activeEdge)
PeriodLast = Period
Period = Time(ActiveEdge) - ToothTime
ToothTime = Time(ActiveEdge)
ToothCount += 1
TickRate = Period/TicksPerTooth
BlankTimer = Period * BlankingRatio
CrankStatus = HalfSync
ToothCount = AngleSync/TicksPerTooth
Period = PeriodLast
TickRate = Period/TicksPerTooth
BlankTimer = Period * BlankingRatio
EngineAngle = AngleSync
PeriodLast = Period
Period = Time(ActiveEdge) - ToothTime
ToothTime = Time(ActiveEdge)
ToothCount += 1
if (ToothCount == LastRealTooth) then LAST = true
TickRate = Period/TicksPerTooth
BlankTimer = Period * BlankingRatio
MISSCNT = NumberMissing
if ((FirstGap && !CamDetected)||(SecondGap &&
CamDetected) then CrankStatus = Full_Sync
else CrankStatus = Error
StallTimer = (StallPeriod + NumberMissing* Period) at
startpoint Time(activeEdge)
BlankTimer = Period * (NumberMissing + BlankingRatio)
Table 1. Angle Clock System State (continued)
Using the eTPU Angle Clock, Rev. 0
Action
If
Tooth_Period*Gap_Rati
o < PeriodLast
If Active Edge
If timeout (StallTimer)
If ActiveEdge
If timeout (StallTimer)
If ToothCount ==
ToothBeforeGap
If ActiveEdge
If AdjustAngle() //return
If timeout (StallTimer)
If Receive(Signal)
If ActiveEdge
If AdjustAngle() //return
If timeout (StallTimer)
Exit Condition
Freescale Semiconductor
12