Spark retard continued

[Posea, David G, SITS]

Thanks Martin and Jon for the replies. I've checked out the PIC'N'POKE page,
and a few other web resources. One degree of delay is equal to:

60 / (RPM * 360) seconds

and

RPM = 60 / time between pulses

These two simple equations can be scaled in millisecs or uSecs for ease in
working with a PIC controller. But I keep getting lost in the interrupts for
processing 4 inputs triggered by a falling edge. One cycle is the time
between falling edges for one input. Do you think I should zero out TMR0 at
the start of input #1, then use TMR0 to track the time. I.E. Input #1 time =
TMRO at interrupt, Input #2 time = TMR0 at interrupt - Input #1, etc. ??

There has to be a better way of doing that :)

Thanks,
David

-----Original Message-----
From: DIY_EFI-Digest-Owner at efi332.eng.ohio-state.edu
[mailto:DIY_EFI-Digest-Owner at efi332.eng.ohio-state.edu]
Sent: Friday, November 19, 1999 15:00
To: DIY_EFI-Digest at efi332.eng.ohio-state.edu
Subject: DIY_EFI Digest V4 #650



DIY_EFI Digest        Friday, November 19 1999        Volume 04 : Number 650



In this issue:

	Spark retard for EEC-V (DIS)
	flowbench

See the end of the digest for information on subscribing to the 
DIY_EFI or DIY_EFI-Digest mailing lists.

----------------------------------------------------------------------

Date: Fri, 19 Nov 1999 07:41:14 -0500
From: "Posea, David G, SITS" <dposea at att.com>
Subject: Spark retard for EEC-V (DIS)

has anyone thought about building a programmable retard unit for a DIS
ignition. Hopefully one with boost retard built in. I've started developing
some PIC code, but I'm not an electronics type. There seems to be two ways
to go. One is to intercept the crank trigger. It has 35 teeth and one
missing one, for a pulse every 10 degrees. That makes writing the retard
code a little tricky, as more than 10 degrees of retard would span pulses.
The other way is to use the coil triggers as inputs. I'm not sure if 4
identical chips should be used, or if one chip should process all inputs.
Does anyone have any ideas on which way I should go. I'm a programmer by
trade, and the PIC assembly language is pretty easy to work with. Any help
you can offer will be greatly appreciated.


David Posea

------------------------------

Date: Fri, 19 Nov 1999 11:53:09 -0600
From: steve ravet <sravet at arm.com>
Subject: flowbench

Off the top of my head, you'd need a driver circuit for each injector,
and you'd have to modify the software (if you used it) to drive more
than one at a time.  I think it used the parallel port to control the
driver circuit.

- --steve


> Date: Thu, 18 Nov 1999 13:54:27 -0700
> From: Andrew Hunter <huntera at cadvision.com>
> Subject: Fuel Injector Flowbench
> 
> For those of you in the know, would it be possible to run muliple
injectors
> on the Perfomance Engineering Flowbench?
> 
> Thanks,
> Andrew
> 

- --steve

- -- 
Steve Ravet
steve.ravet at arm.com
Advanced Risc Machines, Inc.
www.arm.com

------------------------------

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