The AceBus is a very nice Windows driven assembler. A prototype version is available that is quiet adequate for most projects.

The classic Intel Hex assembler was the basic tool for creating software on the 8051. Unfortunately, it has not been maintained and is DOS driven. It has multiple components including relocatable links. However, two basic items are required to successfully create executable code.

ASM51.exe 

   converts a *.txt or *.asm file to is an OBJect file.

OH.exe 

   converts *.obj to *.hex

First get to a DOS prompt.

The format follows

ASM51 name.txt

OH name.obj

A *.Bat file can be used with macros to make this a simple process.

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