Infineon SP37 - Pll_Ref_Signal_Check(); Description; Actions; Prototype

SP37
Tire Pressure Monitoring Sensor
ROM Library Functions
ROM Library Function Guide 79 Revision 1.0, 2011-12-15
2.17 PLL_Ref_Signal_Check()
2.17.1 Description
This function can be called prior to VCO_Tuning() routine to test the lowest and highest VCO tuning curves that
are disjoint in terms of operating frequencies. If the PLL Lock Detector indicates lock for both of the disjoint VCO
tuning curves, a malfunction of the Crystal Resonator is most likely the source of the fault.
2.17.2 Actions
• Select the lowest tuning curve and check the PLL Lock Detector result
• Select the highest tuning curve and check the PLL Lock Detector result
2.17.3 Prototype
signed char PLL_Ref_Signal_Check(void)
2.17.4 Inputs
2.17.5 Outputs
2.17.6 Resource Usage
Table 78 PLL_Ref_Signal_Check: Input Parameters
Register / Address Type Name Description
None --- --- ---
Table 79 PLL_Ref_Signal_Check: Output values
Register/Address Type Name Description
R7 signed char StatusByte StatusByte:
0: PLL Reference Signal available
-1: No PLL Reference Signal available
Table 80 PLL_Ref_Signal_Check: Resources
Type Used or Modified
Registers R7
SFR ACC, B, PSW, DIVIC, DPTR
Stack 2 Bytes
1)
1) Two additional bytes, not included here, are needed to call the library function