pico-assembler

Pico Assembler is a lightweight assembler written in C for a custom instruction set similar to the 8bit PicoBlaze set. It parses pseudoinstructions and outputs the corresponding machine code.

🧱 Build

git clone https://github.com/vtx100/pico-assembler.git
cd pico-assembler
mkdir build && cd build
cmake ..
cmake --build.

✅ Run

./pico-assembler -i <in_file> -o <out_file> -f <format>

❓ Help

./pico-assembler -h 

📘 Supported instructions

| Instruction     | arg_type     |
|-----------------|--------------|
| `JMP`           | `ADDR`       |
| `JZ`            | `ADDR`       |
| `JNZ`           | `ADDR`       |
| `JC`            | `ADDR`       |
| `JNC`           | `ADDR`       |
| `CALL`          | `ADDR`       |
| `CALLZ`         | `ADDR`       |
| `CALLNZ`        | `ADDR`       |
| `CALLC`         | `ADDR`       |
| `CALLNC`        | `ADDR`       |
| `RET`           | `NO_ARG`     |
| `RETZ`          | `NO_ARG`     |
| `RETNZ`         | `NO_ARG`     |
| `RETC`          | `NO_ARG`     |
| `RETNC`         | `NO_ARG`     |
| `LOAD`          | `REG_ANY`    |
| `AND`           | `REG_ANY`    |
| `OR`            | `REG_ANY`    |
| `XOR`           | `REG_ANY`    |
| `ADD`           | `REG_ANY`    |
| `ADDCY`         | `REG_ANY`    |
| `SUB`           | `REG_ANY`    |
| `SUBCY`         | `REG_ANY`    |
| `SR0`           | `REG`        |
| `SR1`           | `REG`        |
| `SRX`           | `REG`        |
| `SRA`           | `REG`        |
| `RR`            | `REG`        |
| `SL0`           | `REG`        |
| `SL1`           | `REG`        |
| `SLX`           | `REG`        |
| `SLA`           | `REG`        |
| `RL`            | `REG`        |
| `INPUT`         | `REG_REG`    |
| `INPUTP`        | `REG_IMM`    |
| `OUTPUT`        | `REG_REG`    |
| `OUTPUTP`       | `REG_IMM`    |
| `RETE`          | `NO_ARG`     |
| `RETD`          | `NO_ARG`     |
| `INTE`          | `NO_ARG`     |
| `INTD`          | `NO_ARG`     |

Meaning of argument types

• ADDR : Symbol/Label (Defined using # can be either before or after where it is used)
• REG_ANY: allows arguments to be either register/register or register/immediate
• REG: 4 bit unsigned. Passed using: %r and an index in the range [0-15] (Decimal representation only)
• REG_REG: 2 register arguments
• REG_IMM: 1 register argument and 1 immediate value bounded by the maximum unsigned representation on 8 bits.Can be passed as:
  • Decimal : using the prefix !d followed by a decimal number
  • Binary : using the prefix !b followed by a binary number

📝 Output formatters

Currently allows outputting in the following formats:

• vhdlbin : "<line_idx>" => b"<binary_instruction>",
• vhdlhex : "<line_idx>" => x"<hex_instruction>",
• debug

🖊️ How to use

Example : in.txt

ADD %1, %13
ADD %1, !d5
JMP jump
ADD %2, %2
#jump
SUB %2 , !b10100010
INTE

Build using :

./pico-assembler -i in.txt -o out.txt -f debug

Console contents:

[OK]: I/O + TOKEN
[OK]: PARSE
[OK]: LINKING
[OK]: WRITE TO FILE
[pico-assembler] Successfully assembled 'in.txt'. Wrote to 'out.txt'.

Means assembly was successful. Output is in out.txt