Actually, if you want a good "for newbies" kind of logic book get the
old tried and true "TTL Cookbook". This has been around for 25+ years,
but it will get you going on discrete logic.
DLC
Nick Mulder wrote:
> Just reading up on the part ...
>
> Still way behind you in terms of knowing this stuff - really need to
> read up on the basics - logic gates, JK flip flops and the like ...
>
> I'll get down to nutting it out shortly - suspect I'll need to turn
> down the music and draw me a picture with bunnywabbits, truth tables
> etc...
>
> Damn spec sheets are written *too efficiently* for me - nothing but
> the required info huh, no '74LS163 for dummies' or 'rtstofer for
> dummies' for that matter ;)
>
> cheers for the update, imagine I would have been quite confused without it !
> Nick
>
> On 7/20/07, rtstofer <rstofer@pacbell.
>
>>--- In oopic@yahoogroups.
>>
>>>If you use a counter with a synchronous reset (reset occurs at clock
>>>edge) then things get a lot easier.
>>>
>>>Consider 2 74LS163 4 bit synchronous counters. Clock both together.
>>>Connect the Ripple Carry Output of the low order counter to the Enable
>>>T input of the high order counter. Ground the Enable T input of the
>>>low order counter. Ground all the Data inputs, the Enable P inputs
>>>and the Load inputs.
>>>
>>>Now, decode Q4 (the low order bit of the high order counter) AND Q3
>>>(the high order bit of the low order counter) as a count of 24 and run
>>>that to the Reset input. The counters will now count 0..24.
>>>
>>>Since you have decoded the 25th count (count = 24) all you have to do
>>>is decode the 13th count (0..12) so: AND together Q3 and Q2 (the high
>>>two bits of the low order counter).
>>
>>OOPS! The count of 24 will last for 1 clock because the counter
>>resets but the count of 12 will last a lot longer - 4 clocks.
>>
>>The proper decode for count = 12 (13th pulse) is Q3 AND Q2 AND (Q1 NOR
>>Q0).
>>
>>
>>>Richard
>>>
>>
>>
>>
>>
>>
>>Yahoo! Groups Links
>>
>>
>>
>>
>
>
>
>
> Yahoo! Groups Links
>
>
>
--
------------
Dennis Clark ooPIC Tech Support
www.oopic.com
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