This is an assembler that takes custom, user-defined instruction sets
and uses them to assemble source files.
It can be useful, for example, if you're trying to test the bytecode of a new virtual machine,
or if you're eager to write programs for that new microprocessor architecture
you just implemented in an FPGA chip!
đĨī¸ Try it right now on your browser!
đšī¸ Check out an example project which targets the NES!
â¨ī¸ Install the VSCode syntax highlight extension!
đ Check out the wiki for a changelog, details on advanced features, and a how-to guide!
You can install directly from crates.io by running cargo install customasm.
Then the customasm application should automatically become available in your
command-line environment.
You can also download pre-built executables from the Releases section.
You can compile from source yourself by first cloning the repository and
then simply running cargo build.
There's also a battery of tests available at cargo test.
đ Check out instructions for migration from older versions to v0.11!
Given the following file:
```asm
{
load r1, {value} => 0x11 @ value8
load r2, {value} => 0x12 @ value8
load r3, {value} => 0x13 @ value8
add r1, r2 => 0x21
sub r3, {value} => 0x33 @ value8
jnz {address} => 0x40 @ address`16
ret => 0x50
}
multiply3x4: load r1, 0 load r2, 3 load r3, 4
.loop:
add r1, r2
sub r3, 1
jnz .loop
ret
```
...the assembler will use the #ruledef directive to convert the
instructions into binary code:
```asm outp | addr | data
0:0 | 0 | ; multiply3x4: 0:0 | 0 | 11 00 ; load r1, 0 2:0 | 2 | 12 03 ; load r2, 3 4:0 | 4 | 13 04 ; load r3, 4 6:0 | 6 | ; .loop: 6:0 | 6 | 21 ; add r1, r2 7:0 | 7 | 33 01 ; sub r3, 1 9:0 | 9 | 40 00 06 ; jnz .loop c:0 | c | 50 ; ret ```
```
Usage: customasm [options]
Options: -f, --format FORMAT The format of the output file. Possible formats: binary, annotated, annotatedbin, binstr, hexstr, bindump, hexdump, mif, intelhex, deccomma, hexcomma, decspace, hexspace, decc, hexc, logisim8, logisim16, addrspan -o, --output [FILE] The name of the output file. --symbol-format SYMBOL-FORMAT The format of the symbol file. Possible formats: default, mesen-mlb -s, --symbol [FILE] The name of the output symbol file. -t, --iter [NUM] The max number of passes the assembler will attempt (default: 10). -p, --print Print output to stdout instead of writing to a file. -q, --quiet Suppress progress reports. -v, --version Display version information. -h, --help Display this information. ```