How to Design Various 4-bit Counters with Direction Inputs?

[olimain]

Please help me urgently - D-Type Latch problem

Hi all,

I have just descovered this wonderful forum and am hoping you can save my degree! I have to have this problem finished in a matter of hours and just can't figure out the schematics/truth tables. Please please please take the time to help in any way with any part if you can - it shouldn't be too hard for some of you experts and I would be eternally grateful. Thanks in advance,

Oliver

Here are the tasks:

Design 1
Design a 4-bit BCD counter that counts from 0 to 9. After 9 the counter should cycle through the same sequence again.

Design 2
Design a 4-bit binary counter which counts in binary from 0 to 15 then cycles through the same sequence again.

Design 3
Design a 4-bit BCD counter that has a direction input (which determines the direction of the count). If direction = 0 the counter should count down, alternatively if direction = 1 then the counter counts up. The input may change at any time and the count must change appropriately at the next clock edge.

Design 4
Design a 4-bit binary counter that has a direction input (which determines the direction of the count). If direction = 0 the counter should count down, alternatively if direction = 1 then the counter counts up. The input may change at any time and the count must change appropriately at the next clock edge.

 

[Gokul43201]

olimain : please read the sticky thread at the top of this subforum, or the forum guidelines that you agreed to before entering (see my signature).

 

[olimain]

Thanks, and I do know I should have posted this well in advance, however I have only just come across this website and hoped I may get lucky.

Apologies.

O