Chapter 27.

M68HC11 and M68HC12 Dependent Features

27.1. M68HC11 and M68HC12 Options

The Motorola 68HC11 and 68HC12 version of

as

have a few machine dependent options.

 m68hc11

This option switches the assembler in the M68HC11 mode. In this mode, the assembler only

accepts 68HC11 operands and mnemonics. It produces code for the 68HC11.

 m68hc12

This option switches the assembler in the M68HC12 mode. In this mode, the assembler also

accepts 68HC12 operands and mnemonics. It produces code for the 68HC12. A few 68HC11

instructions are replaced by some 68HC12 instructions as recommended by Motorola specifica 

tions.

 m68hcs12

This option switches the assembler in the M68HCS12 mode. This mode is similar to

 m68hc12

but specifies to assemble for the 68HCS12 series. The only difference is on the assembling of the

movb

and

movw

instruction when a PC relative operand is used.

 mshort

This option controls the ABI and indicates to use a 16 bit integer ABI. It has no effect on the

assembled instructions. This is the default.

 mlong

This option controls the ABI and indicates to use a 32 bit integer ABI.

 mshort double

This option controls the ABI and indicates to use a 32 bit float ABI. This is the default.

 mlong double

This option controls the ABI and indicates to use a 64 bit float ABI.

 strict direct mode

You can use the

 strict direct mode

option to disable the automatic translation of direct

page mode addressing into extended mode when the instruction does not support direct mode.

For example, the

clr

instruction does not support direct page mode addressing. When it is used

with the direct page mode,

as

will ignore it and generate an absolute addressing. This option

prevents

as

from doing this, and the wrong usage of the direct page mode will raise an error.