Design an asynchronous pacemaker timing circuit using a 555-timer chip. Use the pulse generator circuit below. In particular specify values of the resistors and capacitor that would give a pulse frequency of 70 beats per minute, and pulse widths of 2ms.

I 6 _+vcc 8 Reset Discharg Trigger Threshold 5 I' 4 -10n O/P 1 3 Capacitor Voltage 2/3 Vcc 1/3 Vec Output Voltage T Vcc Charging through R1 and R .Tc Discharging through R tim -TON tt - TD TOFF T 1 = I 2 = 0.7 (R+R) C 0.7 R, C ********