Astable mode of 555 timer

amode_timer555.py

def aFreqCalculate(info):
    r1 = info["r1"]
    r2 = info["r2"]
    c = info["c"]
    t1 = math.log(2) * (r1 + r2) * c  # Time of HIGH
    t2 = math.log(2) * r2 * c         # Time of LOW
    total = t1 + t2
    freq = 1 / total
    duty = t1 / total
    print "R1: %d, R2: %d, C: %f¥n¥tHIGH:%f + LOW:%f = TOTAL:%f(sec)" ¥
          % (r1, r2, c, t1, t2, total)
    print "¥tFreq: %f(Hz)¥n¥tDuty: %f" % (freq, duty)
    # math.log(2) = 0.693


def aResisterCalculate(info):
    f = info["freq"]
    d = info["duty"]
    c = info["c"]
    r1 = (2 * d - 1) / (f * c * math.log(2))
    r2 = (1 - d) / (f * c * math.log(2))
    print "Freq: %f(Hz), Duty: %f, C: %f" % (f, d, c)
    print "¥tR1: %f, R2: %f¥n¥tTOTAL: %f(sec)" % (r1, r2, 1 / f)