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Version: v0.3.7

rgbasm(1) — Game Boy assembler

rgbasm [-EhLVvw] [-b chars] [-D name[=value]] [-g chars] [-i path] [-M dependfile] [-o outfile] [-p pad_value] file

The rgbasm program creates an object file from an assembly source file. Its arguments are as follows:

Change the two characters used for binary constants. The defaults are 01.
Add string symbol to the compiled source code. This is equivalent to name EQUS "value" in code. If a value is not specified, a value of 1 is given.
Export all labels, including unreferenced and local labels.
Change the four characters used for binary constants. The defaults are 0123.
By default, rgbasm inserts a ‘nop’ instruction immediately after any ‘halt’ instruction. The -h option disables this behavior.
Add an include path.
Disable the optimization that turns loads of the form into the opcode in order to have full control of the result in the final ROM.
Print make(1) dependencies to dependfile.
Write an object file to the given filename.
When padding an image, pad with this value. The default is 0x00.
Print the version of the program and exit.
Be verbose.
Disable warning output.

Assembling a basic source file is simple:

$ rgbasm -o bar.o foo.asm

The resulting object file is not yet a usable ROM image — it must first be run through rgblink(1) and rgbfix(1).

rgbasm(5), rgbfix(1), rgblink(1), rgbds(5), rgbds(7), gbz80(7)

rgbasm was originally written by Carsten Sørensen as part of the ASMotor package, and was later packaged in RGBDS by Justin Lloyd. It is now maintained by a number of contributors at