bcd counter

[yeu]

i'm hard up in making the wiring diagram of the bcd counter... my instructor required us to make use of relays (not ic's)

any help will be very much appreciated. thanks!

 

[rjvh]

bcd stands for what???


Robert-Jan

 

[Boncuk]

bcd stands for what???


Robert-Jan

binary to decimal

 

[PGrogan]

In fact, BCD stands for Binary Coded Decimal. For those who don't know what it is, (if there are some) each decimal digit is represented on 4 bits, (0 to 9) so if you want to represent 56, the byte will be 01010110.

 

[silvarblade]

Thanks PGrogan! Very enlightening!Now lets get to the topic.Yeu ,why would your teacher tell you to make a counter with relays(if thats possible)??if it does work out it will have to use active components(surely) and will be useless!

 

[blueroomelectronics]

Teacher must have gotten a bag of relays on eBay.

 

[PGrogan]

I have two things to say :
1) How many relay do you have to make this BCD counter?
2) Good luck! I tried to figure it myself. The first thing to know is how to maintain when an impulse arrive. To do this, you need one more relay on each section (see my figure). The seconde thing to do is the be able to make the relay switch AND maintain on impulse. The third thing is to make an adder with this!

The figure shows two relays with one as an auto-maintain relay. When the button is pushed, the first relay close and make the circuit close between Vcc and ground. As it is done, the second relay makes another road to ground. So, when the button is released, the second relay remain close.

(sorry for my bad english)

 

[yeu]

20 relays. i'm mad i have been trying to figure it out for a couple of days.

 

[silvarblade]

I do get the retaining part but what if we want to open it?except restarting it.

 

[PGrogan]

That is the problem! I did not find any solution using relays only... maybe adding a NC relay on the left leg that will cut the link to ground... but I don't think it will work...

 

[blueroomelectronics]

With 415 Relays you can make Harry Porter's Relay Computer. Pretty sure it can do BCD conversion.
**broken link removed**

 

[ericgibbs]

20 relays. i'm mad i have been trying to figure it out for a couple of days.

hi,
Look at the first item on this link. The *.pdf is 8meg

**broken link removed**