Feeler: Open Source OBC Firmware

[M3C]

1.Are all the stock factory functions remaining the same and functional on the OBC (Ext. temp, Consum, Avg speed, Limit, etc...)?

2.What new functions-features are added?

[Morgion]

1.Are all the stock factory functions remaining the same and functional on the OBC (Ext. temp, Consum, Avg speed, Limit, etc...)?

2.What new functions-features are added?

1. The same? Yes, but enhanced. Functional? Of course. Also way easier to access.

2. Work in progress, but adding connections to additional sensors has been talked about, as well as various calculations and timers (0-60 times etc.) and fault code reading.

[nuvola rossa]

I'll throw it here, didn't read all the posts from long time...

what about can bus support? I mean what if one has a standalone ecu or a datalogger that can send every info through can bus to be displayed?

I bet is too much of a niche

[Morgion]

I'll throw it here, didn't read all the posts from long time...

what about can bus support? I mean what if one has a standalone ecu or a datalogger that can send every info through can bus to be displayed?

I bet is too much of a niche

There was some talk about that but I don't remember what the conclusion was.

[Nomade30]

With USB hosting you can implement software to gather information for datalogging/displaying information from a standalone. The problem is it might be hard to communicate with the ECU without open source, megasquirt might be the only option for this besides stock ECU.

[daandaman]

Is it possible and How hard would it be programming wise for a noob to display 6 temperatures simultaneously that are provided by a Pico TC-08 via USB? (Thermocouple logger with 8 channel input. We have ready to use EGT connections in our euro S50B32 headers.
Same question but then trough programmable analog or serial output of two innovate LC 01 wideband lambda controllers?
Last one; boost pressure?

Will it have programmable outputs to drive or control valves or relays or stepper motors?

That would be my real purpose

[benemorius]

I'll throw it here, didn't read all the posts from long time...

what about can bus support? I mean what if one has a standalone ecu or a datalogger that can send every info through can bus to be displayed?

I bet is too much of a niche

Do you mean actual can bus or just some form of communication? There are some can peripherals in the microcontroller but I don't think I brought any of them out to header pins in this revision. I probably could do that in the next one if that would be desirable.

Is it possible and How hard would it be programming wise for a noob to display 6 temperatures simultaneously that are provided by a Pico TC-08 via USB? (Thermocouple logger with 8 channel input. We have ready to use EGT connections in our euro S50B32 headers.
Same question but then trough programmable analog or serial output of two innovate LC 01 wideband lambda controllers?
Last one; boost pressure?

Will it have programmable outputs to drive or control valves or relays or stepper motors?

That would be my real purpose

Whether it is possible will depend on how the manufacturer implemented the usb communications and how much information they will provide about it. It is likely, though not certain, that they chose to simply use a uart-usb bridge and stream the data out continuously. If that's the case it would be very easy and they wouldn't need to provide any additional information.

How easy it would be for a noob to implement will depend on what sort of code base, development environment, and community we end up with in the weeks and months to come. I'm hoping to make it arduino-easy and I do believe that's an achievable goal.

I have added a number of additional headers on the board for end-user customization. Analog inputs and general purpose i/o are included. Some additional circuitry will be desirable in some cases, but you'll be free to interface with anything you like, including everything you've mentioned.

[m2pc]

@Benemorius, got my prototype board in the mail from you, great job! I can't wait to install and start experimenting!

[silverbullet21]

^^^^^wish there was a way to 'like' this^^^

[daandaman]

[stefanom3]

people are so lazy these days... they just wanna click on a button instead of writing something

Sent using Tapatalk 2

[benemorius]

Looks like the mbed team is working on support for a $35 3g usb device. This could be pretty exciting depending on how open it is. I think I read something about the source being released this month.

http://mbed.org/handbook/Vodafone
http://mbed.org/cookbook/VodafoneUSBModem
http://mbed.org/forum/mbed/topic/3596/

[benemorius]

Here is some information on the two boards that went to m2pc and vollosso:

The firmware they shipped with was commit fbca101 of the repo I posted earlier. It is not a drop-in replacement for the factory firmware, but it does test all or most of the functionality. You can install it in the car and push the buttons to test various functions. The 1000 and 100 buttons cycle through the different relay driver outputs. Everything else is probably self-explanatory. You can look in OpenOBC.cpp at the switch(displayMode) block and the OpenOBC::buttonXXXX() methods to see exactly what each button should do. Some buttons do nothing. To add another button action, be sure to visit line 174 in addition to the other two locations. Also my temp button is broken so the button mask for it is missing.

The only function I know for sure (there may be others that I didn't think of) that can't be tested with a button push is the diagnostic bus communication. I had been testing it by a different means and I simply neglected to enable a button for it and didn't realize it until now. There is however an if(0) block at line 224 in OpenOBC.cpp which, if changed to if(1) (or while(1)) will cause it to send a test query to the body electronics module (zke4) and check for a reply.

Now I remember that there was something interesting about the cover on the 20 pin diagnostic port under the hood but I don't know if we reached anything conclusive about it. I'm pretty sure that I have to leave my cap (1994 325, US) disconnected to use the diagnostic bus as it applies dead short pullups to the two bus wires when installed. I'm not sure where my cap is or I'd confirm that right now. I seem to recall that newer caps may have an additional short which does need to be there to use the diagnostic bus in addition to the pullup shorts which need to not be there. Additional investigation is required here. Note that I did design the diagnostic interface to be safe in the event of a shorted bus, so no damage will result from any wires that the cap shorts when it's installed. It is safe to try it with and without the cap, and I'm interested to hear the results of both. I don't know whether everyone has the same zke4 module in their car for the test. It's been a while and it's all a bit fuzzy still.

I'm attaching a bill of materials. I believe that it's complete and correct for the two boards that went out, human error aside.

Also, as a matter of record, the schematic and gerbers are attached as well.

I've had to mangle the extensions in order to upload them of course. Remove the .txt from the csv file and remove the .pdf from the zip file.

I'm excited to hear how it goes with these boards. Pending some feedback, I'd like to begin considering the next hardware revision immediately.

[johnf]

Now I remember that there was something interesting about the cover on the 20 pin diagnostic port under the hood.... I'm pretty sure that I have to leave my cap (1994 325, US) disconnected to use the diagnostic bus as it applies dead short pullups to the two bus wires when installed....

I also noticed that when we were helping Jim Conforti develop his Shark Injector.

Looks like the mbed team is working on support for a $35 3g usb device. This could be pretty exciting depending on how open it is. I think I read something about the source being released this month....

I'm considering one for an NTP-based master clock (Mutteruhr). I wonder how much standby/quiescent current it will draw.

[vollosso]

Finally got it, what a disaster paypal is.
Will start working on it very soon. I has been a while since I have done development work so I pulled out an old book you two should know "Programming Embedded systems in c and c++" by Michael Barr.
Also a note, my buddy who does development for siemens is going to help me have some fun with this.

[johnf]

As much as I still like C, with 512 Kbytes on board, I would use C to create a minimal portability layer and write pretty much everything else (perhaps the other 90%) in Lua.

[daandaman]

You guys are my nerdy heroes for sure. Amongst most people I know, usually it is me who fills in that role. Now I know how they feel!

[benemorius]

Anyone know much about charging smartphones from usb ports and the D+ D- voltage divider trickery involved?

I'm interested in making sure that the usb host port is capable of charging any device that one might plug in to it. I think I'm going to plan for a max current of 2 amps but I'm not sure what to do with the D+ and D- pins given that the usb port needs to remain functional while still allowing devices to charge at up to their max rated current.

It would seem that high-power devices expect to see certain voltages on the data pins set by voltage dividers. That's all fine and well but it would be nice to avoid a bunch of ugly switchable pullup/pulldown resistors in an already cramped design if possible. Does anyone know if you can get a device (smartphone, ipad, etc.) to switch to high-current charging by enumerating and communicating with it rather than putting voltage dividers on the data pins?

http://voltaicsystems.com/blog/choos...nes-and-ipads/
http://forums.adafruit.com/viewtopic.php?f=8&t=30249

[Morgion]

You can charge the device with a standard USB port (try it - plug your smartphone into your PC and it starts charging), it's just a tad bit slower than charging through an actual USB charger due to less current. Anyway, a standard USB port with no modification whatsoever has enough juice to power a smartphone or a GPS device in use while charging it at the same time, so unless the idea is to get a high-speed recharging slot, I wouldn't worry about the USB port. Just get one of those cigarette lighter 12v chargers or one of those USB charging slots you can inlay in your car's interior plastics and wire into something.

I made meself one of these:


It even has a bi-color LED that changes into orange when there's a device connected.

[benemorius]

You can charge the device with a standard USB port (try it - plug your smartphone into your PC and it starts charging), it's just a tad bit slower than charging through an actual USB charger due to less current. Anyway, a standard USB port with no modification whatsoever has enough juice to power a smartphone or a GPS device in use while charging it at the same time, so unless the idea is to get a high-speed recharging slot, I wouldn't worry about the USB port. Just get one of those cigarette lighter 12v chargers or one of those USB charging slots you can inlay in your car's interior plastics and wire into something.

I made meself one of these:
[img]break http://i.imgur.com/wZFvk.jpg[/img]

It even has a bi-color LED that changes into orange when there's a device connected.

Nice job.

The idea is indeed to achieve high-speed charging. A normal usb port will only charge at a maximum of 500mA. Today's smartphones and other devices have come to require more than this. It's not actually such a small difference. A common standard charging rate these days is 1000mA, so a normal usb port will charge only half as fast. I hear the ipad charges normally at 2100mA - 4 times faster than a normal usb port will allow. And the real trouble is that if you're actually using the device, there may very well not be enough current left to put in the battery if you're limited to 500mA. My phone for instance (a galaxy nexus) will not charge at all if I have it plugged in to a 500mA usb port while the wifi and 3g radios and backlight are active. Rather, it actually slowly discharges.

In any case, the charging speed alone is not what concerns me. It is easy to get a usb port to tell a phone to charge at a higher rate. I linked to some information in my last post. What I'm not sure about is how to also use that same usb port for actual usb communications. Ideally, the openobc will have one usb port to be used for plugging in usb flash drives and smartphones alike. I want to make sure that if you plug in an ipad, you can play music from it while also charging it at its maximum rate of 2.1A.

[stefanom3]

My phone for instance (a galaxy nexus) will not charge at all if I have it plugged in to a 500mA usb port while the wifi and 3g radios and backlight are active. Rather, it actually slowly discharges.

I also noticed that and it's pretty annoying when I use it as a GPS while traveling.

[Morgion]

I have a HTC Desire Z and I have been charging it off laptops etc. while using GPS or tethering while traveling, but it has never lost any battery, although it takes ages for the battery to actually charge any meaningful amount unless the phone isn't in use. So it seems it uses less than 500mA when in use.

[daandaman]

As long as its USB port can be used to communicate with the Pico TC-08 I'm happy. (Really well priced 8 channel thermocouple datalogger from which I will use 6 in the exhaust)

Please check out the site there are packages downloadable with code in different language's! I'd eventuality need your help with that anyways.

[benemorius]

As long as its USB port can be used to communicate with the Pico TC-08 I'm happy. (Really well priced 8 channel thermocouple datalogger from which I will use 6 in the exhaust)

Please check out the site there are packages downloadable with code in different language's! I'd eventuality need your help with that anyways.

http://www.picotech.com/thermocouple.html

Looks like the linux drivers are not only opensource, but are in fact clean and well commented. That's good news. It pretty much means it's a done deal provided that someone is willing to port it to the openobc platform. Hopefully there's a usb guru lurking out there. I don't have a great deal of experience with it.

[daandaman]

So how is the testing going guys?