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Quote:
Originally Posted by Jonny H View Post
Let's clear a few things up:

'Firmware' is generally used to describe code that is 'embedded' in a device, but yes at the end of the day it is still software

Things may be cheaper in the US but in the UK right now (all prices before tax and shipping):

Permatune. 494
MSD 6AL-2 + blaster coil . 505
Original Bosch (used). 400 - 600
Classic Retrofit. 795 - 995
Elf ignition. 900 - 1200
Porsche Original OEM Bosch. 2400

All our units are made in the UK, hand assembled, soak tested and setup per customer requirements in house.

In some cases firmware does not correlate with/to software, FPGA configuration memory download, for instance.

Example: Strobe Data Osprey QXP

FPGA configuration is down loaded with each power on cycle.
Old 03-15-2016, 12:49 PM
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Originally Posted by Jonny H View Post
Ok, my patience is wearing a bit thin but I will attempt explain, again, why we move the input trigger point.

Mr West is describing a 'predictive timing' scheme whereby the ECU tries to 'guess' when the next spark should occur.

At the most simplistic level, this is done by making an assumption that the next spark will occur in the same time interval as the last timing gap measured.

More complex systems, use a predictive algorithm which needs to be 'tuned' as most are based on a (sort of) PID contoller.

Predictive systems cannot cope well with rapid changes in RPM.

In this case we need to define "rapid". Even a relatively inexpensive microprocessor, $2-3, would have enough computing power/capability to "predict" the next firing point based on a multiplicity of parameters, including rate of rise, or fall, in RPM.

They tend to lag and then overshoot.

Only if the selected microprocessor instruction execution rate is too slow for the task (tasks ?) at hand, or the multi-tasking burden is so great that not enough time is left for proper computation of the various parameters involved. I would guess the latter in the case of the CDI+ design.

They also do not work very well if there are not a sufficient number of triggers in the engine rotation to calculate the time interval and that is why these systems typically require the use of a toothed timing wheel (more triggers per rotation). As our system uses the points/VR, we have only six trigger points. We have tried out a predictive scheme but the results were poor. The engine idle was unsteady and the pickup was unresponsive.

The only way to guarantee that the timing is accurate is to move the trigger point forward in time

so you are always calculating a hold off ahead of the cylinder you want to fire.

So, how does your 10 degree predictive timing computation differ from the 60 degree one? That 10% advance trigger input time to plug firing varies greatly in timing from 800 RPM to 7000 RPM! So your programming must use current RPM as a computational parameter, and done correctly would have a parameter for rate of RPM rise/fall parameter.


It isn't adjusting changing the ignition timing, it's moving the trigger point. This is no different in fact to fitting a Pertronix where you have to re-time the engine.

The timing compensation is primarily concerned with dialing out any delay caused by input filtering. Nothing to do with the microprocessor.

The firmware updates are about adding features. Since the product was launched we have added:

1) Tacho smoothing
2) Distributor input smoothing
3) MFI fuel pump cut-off control
4) Configuration of interval between dual sparks
5) Configurable number of triggers before first spark
6) Programmable output / shift light control. Inversion etc.

None of those affect the main operation of the unit and many customers are still on version 1.0.

We are looking at being able to read a MAP sensor from an input and also driving an additional fuel injector from an output.
90% would be my guess as to the number of modern automotive engine control systems that use a SINGLE pulse for each 360 degree crankshaft rotation to compute the timing of ignition and fuel injection.

This can most easily be facilitated via a single dedicated microprocessor ($2-3 cost) or if multi-tasking is a requirement, a more expensive, $20-30, interrupt driven microprocessor.

Why would one not use hardware (simple, straight forward design) for distributor input "smoothing"..?

And why, with input already "smoothed" would one need tacho output signal "smoothing"? The tach, being a mechanical device, has a relatively long time constant for responding to a "dithering" input.

Last edited by wwest; 03-15-2016 at 02:03 PM..
Old 03-15-2016, 01:41 PM
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Jonny

Don't engage with him - no matter what you write he will pick fault - he can't help it as he always has to be the only guy who is right and he does it by letting everyone else know they are wrong.

One day he will grow up and understand that research does not just mean bullying everyone else to their point of view.

In the mean time just ignore him - we all do.

And keep up the interesting work. If the results are good it will sell itself.

Tim
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Old 03-15-2016, 01:52 PM
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Quote:
Originally Posted by wwest View Post
In some cases firmware does not correlate with/to software, FPGA configuration memory download, for instance.

Example: Strobe Data Osprey QXP

FPGA configuration is down loaded with each power on cycle.
That's the very definition of firmware.
Old 03-15-2016, 02:18 PM
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Quote:
Originally Posted by wwest View Post
In some cases firmware does not correlate with/to software, FPGA configuration memory download, for instance.

Example: Strobe Data Osprey QXP

FPGA configuration is down loaded with each power on cycle.
What? Firmware is code which is by nature software. It just happens to be permanent or semi-permanent. Firmware code can control or do any number of things.
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Old 03-15-2016, 02:59 PM
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Yeah, I give up.

Omex, MSD, Megasquirt and many others employ the same 'hold off' scheme we do for timing. It isn't a new thing, been around for ages yet Mr West singles us out for a fight? I just don't get it.

Btw, FPGA config is not firmware as there are no executable instructions, just logic. Now how do I get that stupid wavey smiley? Ah, here it is
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Old 03-15-2016, 03:27 PM
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Originally Posted by Jonny H View Post
Yeah, I give up.

Omex, MSD, Megasquirt and many others employ the same 'hold off' scheme we do for timing. It isn't a new thing, been around for ages yet Mr West singles us out for a fight? I just don't get it.

Btw, FPGA config is not firmware as there are no executable instructions, just logic. Now how do I get that stupid wavey smiley? Ah, here it is
Why does the term "firmware" not apply to a stream of 1's and 0's downloaded to an FPGA...??

And if not then what term is correct?

Yes, it seems that the term "software" always applies to executable code.

And "firmware" seems to apply primary to software that is somehow embedded, executing from ROM, or at power on time transferred from to ram for execution.

Last edited by wwest; 03-15-2016 at 04:54 PM..
Old 03-15-2016, 04:49 PM
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Quote:
Originally Posted by wwest View Post
Why does the term "firmware" not apply to a stream of 1's and 0's downloaded to an FPGA...??

And if not then what term is correct?

Yes, it seems that the term "software" always applies to executable code.

And "firmware" seems to apply primary to software that is somehow embedded, executing from ROM, or at power on time transferred from to ram for execution.
if you could stop polluting threads that would be great
Old 03-15-2016, 04:56 PM
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Quote:
Originally Posted by Jonny H View Post
Yeah, I give up.

Omex, MSD, Megasquirt and many others employ the same 'hold off' scheme we do for timing. It isn't a new thing, been around for ages yet Mr West singles us out for a fight? I just don't get it.

Btw, FPGA config is not firmware as there are no executable instructions, just logic. Now how do I get that stupid wavey smiley? Ah, here it is
I'm not so much attacking your product as your descripotion of how it works.

Again, what is the difference between your CDI+'s 10 degree computed "guess" as to when the next plug firing should occur vs a 60 degree (6 cylinder) "guess" or even a 360 degree "guess".
Old 03-15-2016, 05:01 PM
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I'm going to go out on a limb here and make you a bet. I'm betting that if you check with the lead CDI+ designer that you will find....

A dual rank hardware down count register pair, one of which is currently in active use, triggered by the 10 degree advance distributor signal, and triggering the spark circuit upon reaching zero count. The second register will be pre-loaded with the results of the computed "guess". Those results computed based on the previous time period between firings, adjusted by a parameter reflecting the rate of rise or fall of RPM.

Once a plug firing occurs the second register is loaded with the new down count value and the cycle begins yet again.

The above hardware implementation would easily free up enough processor time to accomodate multi-tasking routines.
Old 03-15-2016, 05:23 PM
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Getting back on track for his thread, how soon before we see some of the comparisons? This product looks to be just what im looking for as a way to do variable advance/retard timing to fine tune a carb based engine build plus it will benefit from other features over time as you research and develop it further.

Tim
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Old 03-15-2016, 06:45 PM
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Quote:
Originally Posted by wwest View Post
A dual rank hardware down count register pair, one of which is currently in active use, triggered by the 10 degree advance distributor signal, and triggering the spark circuit upon reaching zero count. The second register will be pre-loaded with the results of the computed "guess". Those results computed based on the previous time period between firings, adjusted by a parameter reflecting the rate of rise or fall of RPM.

Once a plug firing occurs the second register is loaded with the new down count value and the cycle begins yet again.

The above hardware implementation would easily free up enough processor time to accomodate multi-tasking routines.
Why don't You build one and see how it works?

You could even use one of those Xilinx gate arrays you imply you know so much about.
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Old 03-15-2016, 07:23 PM
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Jonny

Don't engage with him - no matter what you write he will pick fault - he can't help it as he always has to be the only guy who is right and he does it by letting everyone else know they are wrong.

One day he will grow up and understand that research does not just mean bullying everyone else to their point of view.

In the mean time just ignore him - we all do.

And keep up the interesting work. If the results are good it will sell itself.

Tim
I don't think WWEST will ever grow up, but I do think it is important to ignore him. Many of us have seen his antics for years!!
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Old 03-15-2016, 08:02 PM
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Quote:
Originally Posted by wwest View Post
I'm going to go out on a limb here and make you a bet. I'm betting that if you check with the lead CDI+ designer that you will find....

A dual rank hardware down count register pair, one of which is currently in active use, triggered by the 10 degree advance distributor signal, and triggering the spark circuit upon reaching zero count. The second register will be pre-loaded with the results of the computed "guess". Those results computed based on the previous time period between firings, adjusted by a parameter reflecting the rate of rise or fall of RPM.

Once a plug firing occurs the second register is loaded with the new down count value and the cycle begins yet again.

The above hardware implementation would easily free up enough processor time to accomodate multi-tasking routines.

^ OMG!

Well considering I wrote every line of code in the whole system, I think I know how it is implemented thanks and it isn't as you describe. Spare the lecture.

This 'lead designer' thing is really irritating me. He's implying that I had nothing to do with the design. This is based on one comment I made months ago where I said we had consulted a power supply company for the high voltage section of the circuit. We didn't design the chips on the board either, so shoot us!

When you deal with us, you are dealing with actual engineers that designed the hardware, firmware, software. No smoke, no mirrors.

Dyno report is on its way people. Hang in there.
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Old 03-16-2016, 12:58 AM
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Jonny,

As a software developer, I understand the effort needed. You have many supporters. Please keep going and well done thus far.

Cheers!
Old 03-16-2016, 02:18 AM
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Back on topic and in case anyone was wondering, I received a reply about the top trace.

Last edited by yinbhbu; 03-16-2016 at 05:37 AM..
Old 03-16-2016, 05:33 AM
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Some individuals here maybe have trouble securing an audience in real live, hence they get their soap boxes out on the internet every time there's a chance spewing their wisdom.

We should start a periodic thread about chipping an air conditioner with oil additives to improve multiple spark Kettering ignition systems with optical coils....
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Old 03-16-2016, 06:01 AM
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We should start a periodic thread about chipping an air conditioner with oil additives to improve multiple spark Kettering ignition systems with optical coils....
Yes, every function in life needs to be updated to incorporate a micro-controller no matter
how simple the function is with periodic flash updates OTA, e.g. your cell phone.

Just imagine a micro-controller belt that automatically adjusts its tension at meal time,
or over time as you gain weight. It would have its own app controlled by your cell phone
to adjust its tension without having to actually touch it.
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Old 03-16-2016, 08:40 AM
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I think we all appreciate those that enter the marked making parts for our older cars.
I wouldn't get too excited about the exchange...

So, get a T shirt made with 'Lead Designer' and have a good laugh.
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Old 03-16-2016, 09:28 AM
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+1 on ischmitz and mysocal911 .... software looking for a way to insert itself into every problem of life. And then take on a life of its own by constantly vacuuming in updates.... oooops, sorry for my little spasm ... I can pound out the code, but in my heart I will always be a hardware guy ... ha ha

Last edited by Bob Ashlock; 03-16-2016 at 09:59 AM..
Old 03-16-2016, 09:30 AM
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