Testing the "Speeduino": -

Date	Discussion
March 2023	The Speeduino is fully built and sitting on the bench, with its Arduino Mega 2850 plugged in, - what do you do now? Of course, you will need to plug it into the USB port of a computer, of some sort. It doesn't seem to matter much what sort of machine, Speeduino's needs are light. For mobility, it is best to setup a machine that isn't, or at least doesn't have to be, connected to the Internet. I use an old Laptop, running Microsoft Vista. You may need to read up about suitable USB driver software for which ever machine you're using. It's a fairly arcane subject, often cloaked in "smoke and mirrors", and obviously varies depending on your chosen computer hardware. I used a CH340 driver, which works very well. If you are familiar with the "Arduino World", you can download various programming tools and write programs for it in C++. (Programs are called "Sketches" in the Arduino World because some of the original applications were aimed at the Visual Arts arena!) You can test the Speeduino's inputs and outputs, make its light flash and so on, but YOU DON'T HAVE TO!! One of the benefits of using a Speeduino is that the complete application software is already written. What's more, it is free and has been posted into the Public Domain for you to download and use freely. It was created by Josh Stewart, who I believe lives in Castlemaine in Victoria, which is the heart of the Australian Custom Car fraternity. The software is updated regularly by Josh and others. It is extraordinarily feature rich. It caters for single cylinder motorcycles up to supercharged V8 racing engines, running Nitrous Oxide. And, pretty much, all stops in between. The documentation is generally quite detailed, but it does have some holes, here and there. It sometimes assumes a level of previous knowledge that you may, or may not, have. My background is electronics engineering, and I was a commercial programmer for years, which is helpful. Even so, a significant amount of background reading is almost mandatory. There is also very active Users' Forum, where you can post questions and often get useful answers. I'm not going to duplicate the manual here, suffice to say that there is a program available, called "SpeedyLoader", which will locate the latest copy of the Speeduino application on the Internet and download it for you. It will then compile it and load it onto the Speeduino, via USB, entirely automatically. Setting up the Speeduino, and configuring its myriad of options, needs a program to run on the computer so that you can "talk" to the Speeduino directly. Happily, there is one. It is called Tuner Studio and it too, is free. Although, there is a paid version that includes a host of advanced options for a one-time license of about $75 and is well worth it. I won't go through all Speeduino's options - there are hours of fun, research and head scratching there, for you to enjoy. Remember that the documentation is not too bad and that the Users' Forum is worth joining. Tuner Studio includes a test mode for your Speeduino. It generates signals that enable you to address each of the input and output channels individually, so that you can make sure that they are working properly. If you want to test that your Speeduino can actually drive a fuel injector or ignition coil, then you will need a suitable 12v power supply as well. There are two types of fuel injector. One has a high impedance coil (10-15ohms) whilst the other is low (<2 ohms). Earlier types and those associated with central throttle body type injection, (Often called TBI or CPI), are often Low impedance types and I suspect it has to do with the speed at which they are required to operate and the duty cycle they can support without getting too hot. More modern injectors, and those used in engines where they have separate injectors for each cylinder, are generally high impedance types. Speeduino will drive a high impedance injector directly, but not a low impedance unit. Enter the "Peak & Hold" driver! The P&H driver provides a peak of current (up to 6 amps) to activate the low impedance injector very quickly in the first instance, and then drops the current to around 1 amp just to hold the injector open whilst it delivers the necessary charge of fuel without it getting too hot and burning out. The longest "Peak" period is limited to about 3.9mSec. Circuits for P&H drivers are readily available, and I chose one designed by Jean Bélanger in Canada, who is able to supply a professional quality printed circuit board as well. You can find him at www.jbperf.com. I sourced all the components locally, built the board, added it to my Speeduino, and it all works very well. There is a photograph, in the pictures section of the site, showing the P&H waveform on an oscilloscope. Incidentally, having a dual beam oscilloscope available has been invaluable to be able to check the timing relationships between the injector pulses and the incoming distributor signal, to make sure that they occur at the correct time in relation to the engine cycle. I purchased a DIY oscilloscope kit from www.jyetech.com which is an excellent product, comparatively cheap, easy to build and works very well indeed. Having used Tuner Studio to do some limited testing of the Speeduino, it's time to see how it would perform if it were connected to a real engine. That can be a problem if the engine is not readily accessible or if the Speeduino is not yet set-up well enough to even run the engine. The solution is to build a "Stimulator" or test unit that allows Speeduino to think that it is connected to an engine, whilst you have control over all the inputs. Such a unit is described in detail in a YouTube video that can be found at "Stimulator". It uses a very small variable mark/space signal generator that can be bought on eBay for just a few dollars. The "Stimulator" is quite simple to make, and some photos of the finished unit are in the photo gallery. The Speeduino can then be made to think that it's connected to an engine and all the options readily adjusted to achieve the results you need. When you're satisfied with the set-up, it's time to connect the system to your engine. Good luck!

Date

Discussion

March 2023

The Speeduino is fully built and sitting on the bench, with its Arduino Mega 2850 plugged in, - what do you do now?

Of course, you will need to plug it into the USB port of a computer, of some sort. It doesn't seem to matter much what sort of machine, Speeduino's needs are light. For mobility, it is best to setup a machine that isn't, or at least doesn't have to be, connected to the Internet. I use an old Laptop, running Microsoft Vista. You may need to read up about suitable USB driver software for which ever machine you're using. It's a fairly arcane subject, often cloaked in "smoke and mirrors", and obviously varies depending on your chosen computer hardware. I used a CH340 driver, which works very well.

If you are familiar with the "Arduino World", you can download various programming tools and write programs for it in C++. (Programs are called "Sketches" in the Arduino World because some of the original applications were aimed at the Visual Arts arena!) You can test the Speeduino's inputs and outputs, make its light flash and so on, but YOU DON'T HAVE TO!!

One of the benefits of using a Speeduino is that the complete application software is already written. What's more, it is free and has been posted into the Public Domain for you to download and use freely. It was created by Josh Stewart, who I believe lives in Castlemaine in Victoria, which is the heart of the Australian Custom Car fraternity. The software is updated regularly by Josh and others. It is extraordinarily feature rich. It caters for single cylinder motorcycles up to supercharged V8 racing engines, running Nitrous Oxide. And, pretty much, all stops in between.

The documentation is generally quite detailed, but it does have some holes, here and there. It sometimes assumes a level of previous knowledge that you may, or may not, have. My background is electronics engineering, and I was a commercial programmer for years, which is helpful. Even so, a significant amount of background reading is almost mandatory. There is also very active Users' Forum, where you can post questions and often get useful answers.

I'm not going to duplicate the manual here, suffice to say that there is a program available, called "SpeedyLoader", which will locate the latest copy of the Speeduino application on the Internet and download it for you. It will then compile it and load it onto the Speeduino, via USB, entirely automatically.

Setting up the Speeduino, and configuring its myriad of options, needs a program to run on the computer so that you can "talk" to the Speeduino directly. Happily, there is one. It is called Tuner Studio and it too, is free. Although, there is a paid version that includes a host of advanced options for a one-time license of about $75 and is well worth it. I won't go through all Speeduino's options - there are hours of fun, research and head scratching there, for you to enjoy. Remember that the documentation is not too bad and that the Users' Forum is worth joining.

Tuner Studio includes a test mode for your Speeduino. It generates signals that enable you to address each of the input and output channels individually, so that you can make sure that they are working properly. If you want to test that your Speeduino can actually drive a fuel injector or ignition coil, then you will need a suitable 12v power supply as well.

There are two types of fuel injector. One has a high impedance coil (10-15ohms) whilst the other is low (<2 ohms). Earlier types and those associated with central throttle body type injection, (Often called TBI or CPI), are often Low impedance types and I suspect it has to do with the speed at which they are required to operate and the duty cycle they can support without getting too hot. More modern injectors, and those used in engines where they have separate injectors for each cylinder, are generally high impedance types. Speeduino will drive a high impedance injector directly, but not a low impedance unit.

Enter the "Peak & Hold" driver! The P&H driver provides a peak of current (up to 6 amps) to activate the low impedance injector very quickly in the first instance, and then drops the current to around 1 amp just to hold the injector open whilst it delivers the necessary charge of fuel without it getting too hot and burning out. The longest "Peak" period is limited to about 3.9mSec. Circuits for P&H drivers are readily available, and I chose one designed by Jean Bélanger in Canada, who is able to supply a professional quality printed circuit board as well. You can find him at www.jbperf.com. I sourced all the components locally, built the board, added it to my Speeduino, and it all works very well. There is a photograph, in the pictures section of the site, showing the P&H waveform on an oscilloscope.

Incidentally, having a dual beam oscilloscope available has been invaluable to be able to check the timing relationships between the injector pulses and the incoming distributor signal, to make sure that they occur at the correct time in relation to the engine cycle. I purchased a DIY oscilloscope kit from www.jyetech.com which is an excellent product, comparatively cheap, easy to build and works very well indeed.

Having used Tuner Studio to do some limited testing of the Speeduino, it's time to see how it would perform if it were connected to a real engine. That can be a problem if the engine is not readily accessible or if the Speeduino is not yet set-up well enough to even run the engine. The solution is to build a "Stimulator" or test unit that allows Speeduino to think that it is connected to an engine, whilst you have control over all the inputs. Such a unit is described in detail in a YouTube video that can be found at "Stimulator". It uses a very small variable mark/space signal generator that can be bought on eBay for just a few dollars.

The "Stimulator" is quite simple to make, and some photos of the finished unit are in the photo gallery. The Speeduino can then be made to think that it's connected to an engine and all the options readily adjusted to achieve the results you need. When you're satisfied with the set-up, it's time to connect the system to your engine. Good luck!