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

2.18

VCO_Tuning()

2.18.1

Description

This function selects an appropriate tuning curve for the VCO and enables the PLL. If no proper tuning curve could
be selected the PLL will be disabled before the function returns with an error result.
Notes
1. If RF transmission is not performed immediately after this function is called, it is recommended to disable the
PLL by clearing SFR bit RFC.1[ENPLL] to reduce the current consumption.
2. Re-Calibration of the tuning curve is necessary when
than 70 °C
2.18.2

Actions

• Select appropriate tuning curve
• Enable PLL for a RF transmission
• Wait until PLL is locked
2.18.3

Prototype

signed char VCO_Tuning(void)
2.18.4

Inputs

Table 82 VCO_Tuning: Input Parameters
Register / Address
None
2.18.5

Outputs

VCO_Tuning: Output values
Register/ Address
R7
ROM Library Function Guide
Type Name
void ---
Type Name
signed char StatusByte
Tire Pressure Monitoring Sensor
V
changes more than 800mV or
BAT
Description
---
Description
StatusByte:
0: Success of VCO Tuning
-1: VCO Tuning not successful, PLL disabled
-2: XTAL not enabled (crystal required)
81
SP37
ROM Library Functions
T
changes more
Ambient
Revision 1.0, 2011-12-15