Examples

Library Examples

Multiplication Library (multiply.dsa)

// multiply.dsa
// usage:
//
// include multiply "<relative path>"
//
// usage for multiply:
// push (arg1)
// push (arg0)
// call multiply::multiply
// pop (arg0)
// pop (arg1)

multiply:
    push bpr
    mov spr, bpr

    ldw bpr, rg0, 8  // load op 1
    ldw bpr, rg1, 12 // load op 2

    lli 0, acc      // initialize accumulator

start:	
    add acc, rg0, acc
    dec rg1

    cmp rg1, zero
    jgt start

end:
    stw acc, bpr, 8  // store result for caller
    mov bpr, spr
    pop bpr
    return

Print Library (print.dsa)

// print.dsa
// usage:
//
// include print "<relative path>"
//      
// usage for print:
//      push (register containing address of string)
//      call print::print
//      pop zero
//
// usage for reset:
//      call print::reset

dw display: 0x20000
dw current: 0x20000

// prints the given text to the screen.
print:
    push bpr
    mov spr, bpr

    ldw bpr, rg0, 8    // get string address argument
    ldw current, rg1    // get current display position

print_loop:
    ldb rg0, acc
    stb acc, rg1

    iadd rg0, 1
    iadd rg1, 1

    cmp acc, zero
    jne print_loop
    jmp end

// return
end:
    stw rg1, current

    mov bpr, spr
    pop bpr
    return

// resets the cursor position on the screen
reset:
    push bpr
    mov spr, bpr
    ldw display, rg1
    stw rg1, current
    mov bpr, spr
    pop bpr
    return

Example Program (main.dsa)

include print "./print.dsa"

dw stack: 0x10000
db string: "'To confuse your enemy, you must first confuse yourself' - Probably Sun Tzu."

init:
    // set up a stack.
    ldw stack, bpr
    mov bpr, spr

start:
    lwi string, rg1

    // push string address argument
    push rg1
    // call print function
    call print::print
    // clean up stack
    pop rg1

    hlt