Car spoiler wing project

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Thread Starter


Joined Dec 27, 2011

I'm working on a project of an elcetorinacly controlled car spoiler. I'm having a bit of problem with controlling the outputs.
The plan:
I will use a 71493 to count the wheel spins using the hall effect and display it as my speed on the 7 seg disp. Now, I want to save the last value of the count before I CLR it with a 555 (in the mean time it's displayed as XFG2) and so, using it with the 74375 to display as the speed on the display. Also further use it in the 7485 to decide if the wing should go up or down (via H bridge). Now my problem is how to save the last counter value before the CLR so it will be displayed (and used for the logic) till the next CLR. What i achieved now displays the count from 0 and up. I only want the so called end result before the CLR to be displayed.

Thanks for the help, if any.



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Joined Mar 24, 2008
I am sorry. The All About Circuits forum Administrative Team has elected not to host discussions of automotive electrical system modifications/enhancements due to safety concerns, the potential of legal ramifications and the possible circumvention of vehicle regulations at the state and federal level.

This thread is against the AAC forum rules, Chapter 6, as seen here:

Automotive modifications of any kind are strictly forbidden. Therefore, this thread will be closed.

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