SWBf_interpreter.lua

-- Inputs
-- b1 = add > +
-- b2 = sub > -
-- b3 = nxt > >
-- b4 = lst > <
-- b5 = stb > [
-- b6 = enb > ]
-- b7 = set > .
-- b8 = nop > do nothing
-- n1 = pos > instruction possition
-- n2 = svl > value to use with set
-- Outputs
-- n1 = tape[index] > tape value at index
-- n2 = rpos > Requested next instruction possition
-- Others
-- tape = memory
-- index = memory possition
-- stbs = pos when all stb calls was made
-- wab = do not execute anything untill next enb
tape = {}
index = 1
stbs = {}
wab = false
function onTick()
    add = input.getBool(1)
    sub = input.getBool(2)
    nxt = input.getBool(3)
    lst = input.getBool(4)
    stb = input.getBool(5)
    enb = input.getBool(6)
    set = input.getBool(7)
    nop = input.getBool(8)
    pos = input.getNumber(1)
    svl = input.getNumber(2)
    if tape[index] == nil then
        tape[index] = 0
    end
    if add and not wab then
        tape[index] = tape[index] + 1
        rpos = pos + 1
    elseif sub and not wab then
        tape[index] = tape[index] - 1
        rpos = pos + 1
    elseif nxt and not wab then
        index = index + 1
        rpos = pos + 1
    elseif lst and not wab then
        index = index - 1
        rpos = pos + 1
    elseif stb and not wab then
        if tape[index] == 0 then
            wab = true
        else
            stbs[#stbs+1] = pos
        end
        rpos = pos + 1
    elseif enb then
        rpos = pos + 1
        if wab == false then
            if tape[index] == 0 then
                stbs[#stbs] = nil
            else
                rpos = stbs[#stbs]
                stbs[#stbs] = nil
            end
        else
            wab = false
        end
    elseif set and not wab then
        rpos = pos + 1
        tape[index] = svl
    elseif nop and not wab then
        rpos = pos + 1
    end
    output.setNumber(2,rpos)
    output.setNumber(1,tape[index])
end