This is a tutorial with calculator to help learn the application of 555 which is a very rare chip innovation. It is simple, versatile, flexible and programmable (by tweaking of pots).
Astable 555 Timer Flasher – Interactive demo
The 555 Astable oscillator gives a square wave output at pin 3, The output drives two LEDs, LED1 lights up when pin 3 is low and LED2 when pin 3 is high.
The 555 can source (LED2) or Sink (LED1) upto 200mA. It can even drive a small motor or lamp with diodes added to protect from inductive kickback. Vary Ra, Rb and Ct and see the change of frequency, period and duty cycle.
The CD4020BC, CD4060BC are 14-stage ripple carry binary counters, and the CD4040BC is a 12-stage ripple carry binary counter. The counters are advanced one count on the negative transition of each clock pulse. The counters are reset to the zero state by a logical “1” at the reset input independent of clock.
CD4040BC, 12-Stage Ripple Carry Binary Counters
CD4060BC, 14-Stage Ripple Carry Binary Counters
CD4060 – 14-Stage Ripple Carry Binary Counters
you can also use a crystal between pin 10 and 11 with two caps 22pF from 10, 11 to gnd and a 10M resistor between 10 and 11 in place of R C network for more precision.
This was a attempt to make a Sequential Timer with ICM7217 of Intersil, even though it worked well, it was not developed beyond the prototype stage or first iteration. Only when a product is made in some numbers, the documentation and designs become clear, streamlined and seasoned.
The PCB and Circuit are not complete. It may give ideas. During this time, as far as i can remember, these were the only large CMOS devices. 8080-85 and Z80 devices consumed lot of power and needed big boards and supplies.
ICM7217 4-Digit, Presettable, LED Up/Down Counter Maxim
Study this, if you are not good at firmware or you need a simple solution, this is still a versatile chip. It is better you make your own PCB. This board can be used for prototyping only.
Timer Circuit pdf
Clock Circuit pdf
The MM5369AA and 3.579545 MHz
I have converted from DOS Orcad to Windows, corrected some mistakes, use with care. Orcad on DOS had a very user friendly interface, it had a near windows like GUI on DOS, when windows did not even exist, It had right mouse button controls too.