Interrupt RPM and Taylors Elapsed time on 18F4620

[Tobias]

One will be fine too, will it ship tomorrow? Not that I don't have faith in DT

[Charles Linquis]

Tobias,

Not that I think there is anything wrong with the way you are doing things, but - I earlier posted a routine that can read virtually any number of tachometers to good accuracy, and to RPMs far past 15000 (if your tach output is the standard 2 pulse/rev) type. It averages over a period, so jitter
isn't a problem.

It is interrupt-driven, and runs totally in the background.

[Tobias]

Did you ever test it on an 18F4620? I found it. I am sure I will have a few questions in the morning.

[Darrel Taylor]

I earlier posted a routine that can read virtually any number of tachometers to good accuracy, and to RPMs far past 15000 (if your tach output is the standard 2 pulse/rev) type.

BEER thief
<br>

[Bruce]

Yep. My order was shipped UPS RED, and should be here tomorrow, so I'll be shooting
your 18F4431 TQFP out by standard Priority Mail. You should be receiving it pretty fast
with you being just down-the-road.

Not that I don't have faith in DT

You should .. he's a real genius at this stuff...

BTW: Your total for the 18F4431 TQFP + shipping is $11.55, which is exactly our cost for
the part + shipping. Just make a Paypal payment in this amount to [email protected]

And, if you need any help using this thing - just ask. I've done a boat-load of commercial
apps with these.

[Tobias]

Thanks check your PayPal acct

[Bruce]

BEER thief

That is just so WRONG ... hit squad has been mobilized....

[Darrel Taylor]

If Charles hadn't done it with DT_INTS, I might have been upset (longer).

But he did ...
More things to simulate.

I might have to send Charles a 6-pack too.
<br>

[Bruce]

You ain't getting off that easy bud .. you still have to prove me wrong, and show a solution to the problem....)

[Darrel Taylor]

Agreed, and accepted.

But just so I'm clear, what I'm proving wrong is that it's a revision or errata sheet problem with the 18F4620 itself.
And that using an 18F4431 will solve it?

In other words, I gotta do it in hardware too?
<br>

[Bruce]

You just have to prove that my recommendations throughout this thread (for this specific controller) were wrong, and show your solution to the problem - using the same controller.

My point thus far has been that this particular controller is doo-doo. Your entry point on this thread stated;

I think you need to clear the timer sooner.

[Charles Linquis]

I rive in China. The address in my bio is just to confuse people.

[Tobias]

Theoretically I should be able to swap oscillators and the problem will be on the 877A. Give me a bit and I will try that.

Here is a link to the one I have on the boards.
http://mouser.com/ProductDetail/Kyoc...XFVfiWpjmqo%3d

[Bruce]

I think Darrel nailed it with the oscillator problem. Nice catch. I just assumed you were
testing different PICs on the same board.

[Tobias]

its the osc. I had no idea there could be that much variance. Can you suggest a better part number?