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#The VC-3600 Assembly Language The following is a summary of the assembly language for the VC3600.

##Statement Format:

An assembly language statement consists of from one to three fields. These are:

• Label - used to reference the statement. It is optional.
• Labels start in column 1, all other fields separated by blanks or tabs.
• Operation Code - a symbolic name for the number machine language op code.
• Operand - Used to supply additional information. For a machine language instruction this a label.

##Symbolic Operation Codes: 01 ADD
02 SUB
03 MULT
04 DIV
05 LOAD
06 STORE
07 READ
08 WRITE
09 B
10 BM
11 BZ
12 BP
13 HALT

##Symbols Labels and operands are from 1 to 10 characters in length, the first of which is a letter and the remaining may be letters and digits.

##Addresses An address may be specified by a label.

##Assembler Language Instructions

• DC - define constant. The constant is a decimal integer placed in the operand field.
• DS - define storage. The operand specifies the number of words of storage to be set aside.
• ORG -define origin. The operand specifies the address at which the translation of the next instruction will be generated,
• END – indicates that there are no additional statements to translate.

##Comments Data after a ";" is a comment.

• Comments may appear anywhere within an instruction or by themselves.
• Blank lines are ignored.

##Case Sensitivity

• All symbols will be case sensitive.
• Operation codes may be written in upper or lower case or some combination of the two.

###Example

The following is an assembler language program which will read in a number "n" and then compute and print the value of n!. org 100
read n
more load n; This is a comment

;Here is a comment that sit on its own line.
mult fac
store fac
load n
sub one
store n
bp more
write fac
halt
n ds 100; just to show that you code can handle big areas.
fac dc 1
one dc 1
test dc 1234 ; show your program can handle big constants.
end