SW006012 Microchip Technology, SW006012 Datasheet - Page 152

• Manufacturer Part Number: SW006012
• Description: C COMPILER FOR DSPIC30F FAMILY
• Manufacturer: Microchip Technology
• Type: MPLAB® C30 Compilerr
• Series: PIC24 & DsPICr

Specifications of SW006012

• Supported Families: PIC24, DsPIC30F And DsPIC33F
• Core Architecture: PIC, DsPIC
• Kit Contents: Software And Docs
• Mcu Supported Families: PIC24 MCUs And DsPIC DSCs
• Tool Type: Compiler
• Processor Series: PIC24, dsPIC
• Lead Free Status / RoHS Status: Not applicable / Not applicable
• For Use With/related Products: dsPIC30F
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

MPLAB
DS51284F-page 146
®
C30 User’s Guide
__
Description:
Prototype:
Argument:
Return Value:
Assembler Opera-
tor / Machine
Instruction:
Error Messages
__
Description:
Prototype:
builtin_msc
builtin_mulss
Computes a x b and subtracts from accumulator; also prefetchs data
ready for a future MAC operation.
xptr may be null to signify no X prefetch to be performed, in which
case the values of xincr and xval are ignored, but required.
yptr may be null to signify no Y prefetch to be performed, in which
case the values of yincr and yval are ignored, but required.
xval and yval nominate the address of a C variable where the
prefetched value will be stored.
xincr and yincr may be the literal values: -6, -4, -2, 0, 2, 4, 6 or an
integer value.
If AWB is non null, the other accumulator will be written back into the
referenced variable.
For example:
might generate:
int __builtin_msc(int a, int b,
a
b
xptr
xval
xincr
yptr
yval
yincr
AWB
Returns the cleared value result to an accumulator.
msc
An error message will be displayed if:
• the result is not an accumulator register
• xval is a null value but xptr is not null
• yval is a null value but yptr is not null
Computes the product p0 x p1. Function arguments are signed inte-
gers, and the function result is a signed long integer. The command-line
option -Wconversions can be used to detect unexpected sign
conversions.
signed long __builtin_mulss(const signed int p0,
const signed int p1);
register int result asm("A");
int *xmemory;
int *ymemory;
int xVal, yVal;
result = __builtin_msc(xVal, yVal,
msc w4*w5, A, [w8]+=2, w4, [w10]+=2, w5
int **xptr, int *xval, int xincr,
int **yptr, int *yval, int yincr, int *AWB);
Integer multiplicand.
Integer multiplier.
Integer pointer to pointer to x prefetch.
Integer pointer to value of x prefetch.
Integer increment value of x prefetch.
Integer pointer to pointer to y prefetch.
Integer pointer to value of y prefetch.
Integer increment value of y prefetch.
Integer pointer to accumulator selection.
&xmemory, &xVal, 2,
&ymemory, &yVal, 2, 0);
© 2007 Microchip Technology Inc.