escala = 1 / 81
zeroX = 160
zeroY = 100
maxiter = 32

CR = -.798
CI = .1618

SCREEN 13
FOR x = 0 TO 2 * zeroX - 1
    FOR y = 0 TO 2 * zeroY - 1
        zreal = (x - zeroX) * escala
        zimag = (zeroY - y) * escala
        FOR iter = 1 TO maxiter
            BR = CR + zreal * zreal - zimag * zimag
            zimag = CI + 2 * zreal * zimag
            zreal = BR
            IF zreal * zreal + zimag * zimag > 4 THEN
                PSET (x, y), 1 + (iter MOD 16)
                EXIT FOR
            END IF
        NEXT iter
    NEXT y
NEXT x
END