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

2.17

PLL_Ref_Signal_Check()

2.17.1

Description

This function can be called prior to
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

Table 78 PLL_Ref_Signal_Check: Input Parameters
Register / Address
None
2.17.5

Outputs

Table 79 PLL_Ref_Signal_Check: Output values
Register/Address
R7
2.17.6

Resource Usage

Table 80 PLL_Ref_Signal_Check: Resources
Type
Registers
SFR
Stack
1) Two additional bytes, not included here, are needed to call the library function
ROM Library Function Guide
VCO_Tuning()
Type Name
--- ---
Type Name
signed char StatusByte
Used or Modified
R7
ACC, B, PSW, DIVIC, DPTR
1)
2 Bytes
Tire Pressure Monitoring Sensor
routine to test the lowest and highest VCO tuning curves that
Description
---
Description
StatusByte:
0: PLL Reference Signal available
-1: No PLL Reference Signal available
79
SP37
ROM Library Functions
Revision 1.0, 2011-12-15