DM-COP8/20D National Semiconductor, DM-COP8/20D Datasheet - Page 35

• Manufacturer Part Number: DM-COP8/20D
• Description: CABLE FOR DEBUG MODULE 20-DIP
• Manufacturer: National Semiconductor

Specifications of DM-COP8/20D

• Accessory Type: 20-DIP Target Cable
• For Use With/related Products: MetaLink Debug Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: *DM-COP8/20D

1. Assembler
2. Assembler Inputs/Outputs
3. Assembler Directives
The assembler is a software program that converts a source program into an
object file. In other words, it converts ASCII representation of instructions to
binary representation.
Source File - ASCII file containing a software program written in instruction
mnemonics (symbolic language).
Object File - "Executable" file containing instruction opcodes (machine lan-
guage).
Listing File - An ASCII file which lists each location in memory and the in-
struction opcode associated with it. It usually contains assembly error mes-
sages. This listing is useful for finding errors, determining size of code,
finding location of segments of code, and checking for proper assembling of in-
structions.
Symbol Table - Table of constants and symbols with their associated values.
It is useful for determining the locations of subroutines in the code.
An assembler directive is an instruction for the assembler in the source file.
Different assemblers have different sets of directives. Examples:
.CHIP Specifies the particular device for which the code is written
.END
.=NUM Sets the location counter to NUM. The location counter is used
.BYTE Tells the assembler to store the following 8-bit value in program
Specifies the end of the code
by the assembler to store the address of the memory location
where the current instruction is being stored. This directive
allows the user to specify a particular location for a given
segment of code.
memory. Tells the assembler not to interpret it as an instruction.
This is useful for storing a table of data.
MICROCONTROLLER BASICS
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