SW500008 Microchip Technology, SW500008 Datasheet - Page 94

• Manufacturer Part Number: SW500008
• Description: PICC-18 STD
• Manufacturer: Microchip Technology
• Type: Compilerr
• Series: PIC18r

Specifications of SW500008

• Supported Families: PIC18
• Core Architecture: PIC
• Software Edition: Standard
• Kit Contents: Software And Docs
• Mcu Supported Families: PIC18
• Tool Function: Compiler
• Tool Type: Compiler
• Lead Free Status / RoHS Status: Not applicable / RoHS Compliant
• For Use With/related Products: PIC18 Series
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 015; 778-1001; 778-1001

Preprocessing
The #pragma regsused directive allows the programmer to indicate register usage for functions
that will not be “seen” by the code generator, for example if they were written in assembly code.
where register_list is a space-separated list of registers names. Those registers not listed are
assumed to be unused by the function or routine. The code generator may use the unlisted registers
to hold values across a function call. Hence, if the routine does in fact use these registers, unreliable
program execution may eventuate.
not recognised. A blank list indicates that the specified function or routine uses no registers.
3.12.3.5 The #pragma switch Directive
Normally the compiler decides the code generation method for switch statements which results in
the smallest possible code size. The #pragma switch directive can be used to force the compiler to
use one particular method. The general form of the switch pragma is:
where switch_type is one of the available switch methods listed in Table 3.14.
80
The general form of the pragma is:
The register names are not case sensitive and a warning will be produced if the register name is
#pragma regsused register_list
#pragma switch switch_type
wreg
status
pclat
prodl, prodh
btemp, btemp+1...btemp+11
xbtemp
fsr0, fsr1, fsr2
switch type
auto
direct
Register Name
Table 3.13: Valid Register Names
Table 3.14: switch types
use smallest code size method (default)
table lookup (fixed delay)
W register
STATUS register
PCLATH register
product result registers
btemp temporary registers 0 to 11
btemp temporary registers 12+
indirect data pointers 0, 1 and 2
description
Description
C Language Features