Holtek HT-IDE, User Manual

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24 0007 1780 R1 sdz BCnt
24 0008 2802 1 jmp ??0000
25 0009 end
0 Errors
Assembly Instructions
The syntax of an instruction has the following form:
[name:] Mnemonic [operand1[,operand2]] [;comment]
where
name:
→
label name
Mnemonic
→
instruction name (keywords)
operand1
→
registers
memory address
operand2
→
registers
memory address
immediate value
Name
A name is made up of letters, digits, and special characters, and is used as
a label.
Mnemonic
Mnemonic is an instruction name dependent upon the type of the microcon-
troller used in the source program. The microcontroller type needs to be
specified prior to the first instruction statement in the source program by
using the directive .CHIP.
Operand, operator and expression
Operands (source or destination) are the argument defining values that are
to be acted on by instructions. They can be constants, variables, registers,
expressions or keywords. When using the instruction statements, care
must be taken to select the correct operand type i.e. source operand or
destination operand. The dollar sign $ is a special operand, namely the
current location operand.
An expression consists of many operands that are combined to describe a
value or a memory location. The combined operators are evaluated at
HT-IDE User’s Guide
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