as has no additional command-line options for the Hitachi H8/500 family.
The following documentation refers to the syntax for the Hitachi H8/500.
! is the line comment character.
; can be used instead of a newline to separate statements.
Since $ has no special meaning, you may use it in symbol names.
You can use the predefined symbols r0, r1, r2, r3, r4, r5, r6, and r7 to refer to the H8/500 registers.
The
H8/500 also has the following control registers.
dp
bp
tp
ep
sr
ccr
All registers are 16 bits long. To represent 32 bit numbers, use two adjacent registers; for distant memory addresses, use one of the segment pointers (cp for the program counter; dp for r0–r3; ep for r4 and r5; and tp for r6 and r7.
as
understands the following addressing modes for the H8/500.
@Rn
@(d:8, Rn)
@(d:16, Rn)
@-Rn
@Rn+
@aa:8
@aa:16
#xx:8
#xx:16
The H8/500 family has no hardware floating point, but the .float directive generates IEEE floating-point numbers for compatibility with other development tools.
as has no machine-dependent directives for the H8/500. However, on this platform the .int and .word directives generate 16-bit numbers.
For detailed information on the H8/500 machine instruction set, see H8/500 Series Programming Manual (Hitachi M21T001).
as implements all the standard H8/500 opcodes. No additional pseudo-instructions are needed on this family.