
SP37
Tire Pressure Monitoring Sensor
Introduction
ROM Library Function Guide
17
Revision 1.0, 2011-12-15
1
Introduction
1.1
General Considerations
This document describes the ROM Library functions that are available in the SP37 Version A5 step device. When
the ROM Library Function
“FW_Revision_Nb()” on Page 101
is called, these devices will return the value 0A32
H
for the ROM revision.
In order for the application to use these ROM Library functions, the following files have to be included to the
software project:
•
SP37_ROMLibrary.h (the header file the function prototypes)
•
SP37_ROMLibrary.lib (the precompiled ROM Library functions)
Notes
1. The application must ensure that no IDLE-RESUME event source is active before any call of the
ROM Library_functions.
2. All typical charge consumptions and typical execution times stated throughout this document were obtained
from measurements of 10 devices at
V
BAT
= 3.0 V and
T
Ambient
= 25°C
3. Analysis of General Register, SFR, and Stack resource usage was performed on object code generated by
Keil uVision3 (Assembler version: 8.00d, Compiler version: 8.08, Linker version: 6.05,
Hex converter version: 2.6.0.1).
1.2
Type definitions
The following table defines the parameter types used throughout this document.
The Keil C51 Compiler stores data in big endian format (MSB first).
1.3
Wakeup Handler
The Wakeup-Handler is executed every time the device wakes up from POWER DOWN state. Possible wakeup
sources are listed in SP37 Datasheet
Table 1
Definition of types
Type
Description
Range
Minimum
Maximum
Unsigned char
8 bit value without sign bit
0
255
Signed char
8 bit value with sign bit
-128
127
Unsigned int
16 bit value without sign bit
0
65,535
Signed int
16 bit value with sign bit
-32,768
32,767
Unsigned long
32 bit value without sign bit
0
4,294,967,295
Signed long
32 bit value with sign bit
-2,147,483,648
2,147,483,647
Table 2
Wakeup Handler
Parameter
Symbol
Values
Unit Note / Test Condition
Min.
Typ. Max.
Wakeup from POWER DOWN state
(independent of Wakeup source)
t
wakeup
–
0.85
1.8
ms