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

2.11

Get_Supply_Voltage()

2.11.1

Description

Get_Supply_Voltage() is the third part of a set of three functions to measure the battery voltage during RF
transmission. It reads the measured value obtained during Trig_Supply_Voltage(), turns off the ADC, and
performs battery voltage compensation. Typically this function is called by the application after the RF
transmission is finished.
2.11.2

Actions

• Read the ADC result register
• Turn off ADC
• Compensate the result for offset using calibration data stored in FLASH
2.11.3

Prototype

unsigned char Get_Supply_Voltage ( signed int idata * Batt_Result )
2.11.4

Inputs

Table 54 Get_Supply_Voltage: Input Parameters
Register / Address
R7
2.11.5

Outputs

Table 55 Get_Supply_Voltage: Output values
Register/ Address
R7
*Batt_Result+0
*Batt_Result+1
ROM Library Function Guide
Type Name
signed int Batt_Result
idata*
Type Name
unsigned char StatusByte
signed int Compensated
battery voltage
signed int Raw battery voltage 10 Bit ADC Result Value:
Tire Pressure Monitoring Sensor
Description
Pointer to an integer array in RAM to receive the
measurement result
Description
0000.0000 : Success
B
xxxx.xxx1 : Underflow of ADC Result
B
xxxx.xx1x : Overflow of ADC Result
B
8000 = -4096.0 mV (Only theoretical number)
H
0000 = 0.0 mV
H
7FFF = 4095.875 mV
H
( = 4096 mV - 1 LSB where 1 LSB = 1/8 mV)
0000.00xx.xxxx.xxxx
66
SP37
ROM Library Functions
B
Revision 1.0, 2011-12-15