45.2.3.1 Extended Instruction Syntax with Standard PIC18 Commands
When the extended instruction set is enabled, the file register
argument, ‘f’, in the standard byte-oriented and bit-oriented commands is replaced with the
literal offset value, ‘k’. As already noted, this occurs only when ‘f’ is less than or
equal to 5Fh
. When an offset value is used, it must be indicated by square
brackets (“[ ]
”). As with the extended instructions, the use of brackets
indicates to the compiler that the value is to be interpreted as an index or an offset.
Omitting the brackets, or using a value greater than 5Fh within brackets, will generate an
error in the MPASM Assembler.
If the index argument is properly bracketed for Indexed Literal
Offset Addressing, the Access RAM argument is never specified; it will automatically be
assumed to be ‘0
’. This is in contrast to standard operation (extended
instruction set disabled) when ‘a’ is set on the basis of the target address. Declaring the
Access RAM bit in this mode will also generate an error in the MPASM Assembler.
The destination argument, ‘d’, functions as before.
In the latest versions of the MPASM Assembler, language support for
the extended instruction set must be explicitly invoked. This is done with either the
command-line option, /y
, or the PE directive in the source listing.