Re: Parallel Card

[bieling@terra.es]

mdj <mdj.mdj@gmail.com> wrote:

> Hi,
> ...
> Just grab two 74LS164's from the local electronics shop. This component
> is an 8-bit shift register. In essence, you connect the reset, clock
> and input pins of a shift register to the annunciators on the game
> port. Each of the 8 outputs is then connected to an LED.

Matt, if you use a '164 the bits at the parallel output will be
shifting
at the same time while the shift-register is being loaded... (not very
useful unless you're Michael Knight :-)

The output has to be isolated somehow from the shift register until the
desired value has been completely shifted in.

A '595 latched shift-register will do the trick: first shift in the
desired value, and then transfer it to the output latch.

-- 
Jorge Chamorro Bieling