# designing 4-bit gray code counter using j-k bistables

A

#### aidanbrennan

i need to design a code using j-k bistables that counts from 0000 to 1111.all other possible states must return to 0000

J

#### Johan Bengtsson

Also check the archives and the other ongoing threads about grey code. (When you search the archives, also search for gray, it was spelled that way in the subject in some thread some time ago)

/Johan Bengtsson

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I

#### iby

i don't know how to do gray code counter
with J-K bistabiles (i wouldn't waste my time
trying to develop one either). just use common
4-bit counter and decode it into gray code.

Iby

#### PhilCorso

Gray is the correct spelling, grey is not. The Gray-code is one of a number of cyclical digital codes in which successive numbers differ by just one bit. Cyclical-codes are prominent in two digital technique areas: analog-to-digital conversion; and digital communication error
detection and correction.

The Gray-code was named after one of the eminent Bell Lab scientists given credit for the study of cyclical codes, Dr. Gray.

If presented in a parallel-bit arrangement, then implementation of "XORs" will suffice. If presented as a serial-bit arrangement, then
Johan's suggestion using the J-K bistable element is one conversion technique.

Regards,
Phil Corso, PE
(Boca Raton, FL)

J

#### Johan Bengtsson

Besides, did you really get the task correctly?
a 4-bit gray counter should really count from 0000 to 1000 and all 16 possible states would then be valid. I see no reason you would want to use gray-code and wrap from 1111 to 0000. Ok it is not that hard doing one but I fail to see the reason for it.

/Johan Bengtsson

----------------------------------------
P&L, Innovation in training
Box 252, S-281 23 H{ssleholm SWEDEN
Tel: +46 451 49 460, Fax: +46 451 89 833
E-mail: [email protected]
Internet: http://www.pol.se/
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