Reference Guide

The Development Library 6-23
Saturn instructions syntax
In this section:
x is a decimal number between 1 and 16. An expression can be used if its value can be determined at the first
encounter.
h is a hexadecimal digit.
a is a decimal number ranging from 1 to 16 or a 0 to 15 number depending of the current mode (0-15 or 1-16).
An expression can be used, if its value can be determined at the first encounter.
f is a field A, B, X, XS, P, WP, M, S, F1, F2, F3, F4, F5, F6 or F7.
Reg is a working register A, B, C or D.
RReg is a scratch register R0, R1, R2, R3 or R4.
Exp is an expression.
Cst is a decimal constant. An expression can be used if its value can be determined at the first encounter.
DReg is a pointer register D0 or D1.
Data is memory data pointed by D0 or D1. It means DAT0 or DAT1 .
Note: For instructions that use two working registers, instruction using the pairs A-B, B-C, C-D and A-C are
smaller and faster (if the Fn fields are not used).
For instructions like Reg1=Reg1… you can write only Reg1… Example: A=A+C.A is the same as A+C.A .
Syntax Example Notes
Reg=0.f
A=0.M
Sets the specific field of the register to 0
Reg=1.f
A=1.M
Sets the specific field of the register to 1
LC hhh..hhh
LA hhh..hhh
LC 80100
LA #1024
The number of nibbles loaded in the register is the number of characters
necessary to write the value. So LC #12 will be equivalent to LC 00C.
Note: the less significant nibble is loaded in the nibble P (as in the value of
the register P) of the register, the next one into nibble p+1 mod 16, and
etcetera.
LCASC(x) chrs
LAASC(x) chrs
LCASC(4) MASD
LAASC(5) ROCKS
Loads the hexadecimal value of x characters into C.
x must be between 1 and 8. See note on LC instruction
LC(x) Exp
LA(x) Exp
LC(5)@Buf+Off
Loads the result of an expression into C or A, using x nibbles.
See note on LC instruction
Reg1=Reg2.f
A=B.X
Copies the value of a specific field of a register into the same field of
another register
Reg1Reg2EX.f
ABEX.W
Exchanges the value of 2 registers on the given field. Note: this is not valid
for the Fn fields
Reg1=Reg1+Reg2.f
Reg1+Reg2.f
A=A+B.A
C+D.A
Adds the value of the specific field of one register to the other register.
Note: If Reg1 and Reg2 are the same, this is a multiply by 2 instruction
Note: This instruction is affected by the DEC/HEX mode only if the field
is not a F field and the registers are AB, BC, CD or AC.
Reg1=Reg1-Reg2.f
Reg1-Reg2.f
A=A-B.A
C-D.A
The following instructions are also available (but not on the Fn fields):
A=B-A. f B=C-B. f
C=A-C. f D=C-D. f
see note on Reg1=Reg1+Reg2.f