Assembler

Software responsible for translating assembly language instructions into their corresponding binary code for execution on the FPGA board.

For example:

Assembly

; Prints "Hello Mom" to the top left of the screen and ends.

jmp main

hello: string "Hello Mom"

main:
    loadn r0, #0     ; r0 = 0
    loadn r1, #hello ; r1 = Pointer to the string to be printed.
    loadn r2, #0     ; r2 = Index for the position on the screen

    printLoop:
        loadi r3, r1     ; Load the character to be printed
        cmp r0, r3       ; and check if it's the terminal character.
        jeq endLoop      ; End if it is or,
        outchar r3, r2   ; otherwise, print it and continue.
        inc r1           ; Increment the pointer to the string.
        inc r2           ; Increment the index for the position on the screen.
        jmp printLoop
    endLoop:
        halt

Binary

-- Code generated by the assembler
WIDTH=16;
DEPTH=65536;
ADDRESS_RADIX=UNS;
DATA_RADIX=BIN;
CONTENT BEGIN
0:0000100000000000;
1:0000000000001100;
2:0000000001001000;
3:0000000001100101;
4:0000000001101100;
5:0000000001101100;
6:0000000001101111;
7:0000000000100000;
8:0000000001101101;
9:0000000001101111;
10:0000000001101101;
11:0000000000000000;
12:1110000000000000;
13:0000000000000000;
14:1110000010000000;
15:0000000000000010;
16:1110000100000000;
17:0000000000000000;
18:1111000110010000;
19:0101100000110000;
20:0000100001000000;
21:0000000000011011;
22:1100100110100000;
23:1001000010000000;
24:1001000100000000;
25:0000100000000000;
26:0000000000010010;
27:0011110000000000;
28:0000000000000000;
29:0000000000000000;
[...]
65533:0000000000000000;
65534:0000000000000000;
65535:0000000000000000;
END;

Installation

The assembler is available in two versions:

• v1.0.0 stable (recommended)
• v2.1.0 beta

To install them, run the following commands:

stable

wget https://github.com/de-abreu/Processador-ICMC/raw/master/assembler/assembler-stable.zip
unzip assembler-stable.zip
cd stable
gcc *.c -o assembler

beta

wget https://github.com/de-abreu/Processador-ICMC/raw/master/assembler/assembler-beta.zip
unzip assembler-beta.zip
cd beta
gcc *.c -o assembler

This will give you the executable assembler. Take it to the directory where you are working, as convenient.

Usage

Without loss of generality, consider an assembly file game.asm. If there are no syntax errors, running the following command will produce the binary file game.mif:

stable

./montador game.asm game.mif

beta

./montador game.asm

Otherwise, if there are syntax errors, a corresponding error message will be issued.

TODO

1. Find and detail the installation for Windows users
2. Detail more assembler usage options