SW006013 Microchip Technology, SW006013 Datasheet - Page 213

• Manufacturer Part Number: SW006013
• Description: MPLAB C Compiler For DsPIC DSCs
• Manufacturer: Microchip Technology
• Series: DsPIC30F/33Fr
• Type: MPLAB® C Compilerr

Specifications of SW006013

• Supported Families: DsPIC30F, DsPIC33F
• Core Architecture: DsPIC
• Kit Contents: Software And Docs
• Mcu Supported Families: DsPIC30F And DsPIC33F
• Tool Function: Compiler
• Tool Type: Compiler
• Processor Series: dsPIC
• Lead Free Status / RoHS Status: na
• For Use With/related Products: dSPIC DSCs
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

5.3
© 2008 Microchip Technology Inc.
<LIBQ.H> MATHEMATICAL FUNCTIONS
The header file
calculate fixed point mathematical operations.
5.3.1
Many functions in this section use fixed-point Q15 (0.15) format, which ranges from
-2
_Q15abs
Description:
Include:
Prototype:
Argument:
Return Value:
_Q15acos
Description:
Include:
Prototype:
Argument:
Return Value:
_Q15acosByPI
Description:
Include:
Prototype:
Argument:
Return Value:
15
to 2
15
-1, or -32768 to 32767. For each function, the entire range may not be used.
Q15 Functions
libq.h
The function finds the absolute value of a Q15 value.
<libq.h>
_Q15 _Q15abs(_Q15 x);
x
2
This function returns the absolute value of x in Q15 format. This value
ranges from 0 to 32767.
This function finds the arc cosine of a Q15 value.
<libq.h>
_Q15 _Q15acos(_Q15 x);
x
2
This function returns the arc cosine of x in Q15 format. This value
ranges from 256 to 32767.
This function finds the arc cosine of a Q15 value and then divides by PI
(π).
<libq.h>
_Q15 _Q15acosByPI(_Q15 x);
x
2
This function returns the arc cosine of x, divided by PI, in Q15 format.
This value ranges from 82 to 32767.
15
15
15
consists of macro definitions and various functions that
-1. The value of this argument ranges from -32768 to 32767.
-1. The value of this argument ranges from 17705 to 32767.
-1. The value of this argument ranges from -32768 to 32767.
a fixed point number in Q15 format, which ranges from -2
a fixed point number in Q15 format, which ranges from -2
a fixed point number in Q15 format, which ranges from -2
DS51456E-page 209
15
15
15
to
to
to