Re: Using the TI LaunchPad from your KoP
 

I will contact you through a private message - we are working with Altium and other formats. Have a few questions trying to get this into CircuitWorks. Marie

Re: Using the TI LaunchPad from your KoP
 

We've been able to return to this issue now that some of our more pressing problems have been resolved. In summary, we have successfully implemented an interrupt-based quadrature encoder that restores that aspect of now-discontinued Enhanced I/O features of the Driver Station.

Whitepaper located here:

http://www.chiefdelphi.com/media/papers/3097

Re: Using the TI LaunchPad from your KoP
 

This is really awesome work!
That's a really lightweight ISR for the encoder, and shouldn't cause any problems with the USB stack.

Re: Using the TI LaunchPad from your KoP
 

Thanks, but now that I think of it we probably should have cleared the interrupt flag *after* incrementing/decrementing the counter instead of before. Nonetheless, it does seem to work OK as-is.

Re: Using the TI LaunchPad from your KoP
 

I know this thread is slightly stale, but it also seems to be the closest thing I can find to the official thread for the LaunchPad.

In as much as I can see that the LaunchPad successfully implements "Output" as well as Input, I have a question.

It is not so much that I am trying to create competition for the LaunchPad, but I am trying to help increase innovation. What I would like to know is, how does the LaunchPad parse the "Output Reports" sent from the DS to the "USB HID" device that the LaunchPad is acting as?

I have done a lot of searching on the Internet and have found almost nothing on the formatting of "output reports" let alone any examples of how to receive and parse these reports.

Specifically I have two devices I would like to use in the exact same manner as the LaunchPad, the Teensy 3.1 and the Leonardo. Thus far. using them as input devices is all I can achieve. It's the output, such as turning on LEDs or force feedback, that I can not seem to be able to do.

I guess there is a second question I would like answered. Is there a document that includes a description of the data formatting sent by the DS to attached USB HID devices?

Re: Using the TI LaunchPad from your KoP
 

I'm guessing you haven't looked at the source code for the Launchpad. That's the only example you should need to find online and it's referenced in this thread I believe. If not, it's on the wiki that is linked from this thread.

Re: Using the TI LaunchPad from your KoP
 

Hey Joe, good to hear from you after CVR. I sure appreciated working with you!

I'll go back and see if that code helps me. You are correct, I haven't looked at it yet. Not being a programmer by trade, more like a hack, if code isn't well commented, it really is mind-bending for me. I need things clearly spelled out before it makes sense.

Re: Using the TI LaunchPad from your KoP
 

Hi Will,
Any progress on the documentation?
Any chance I can do this in Eclipse instead of CCS? I already have Eclipse installed and need to get more familiar with it. If not, I'll just add CCS and follow your document(s) when they are available.

Re: Using the TI LaunchPad from your KoP
 

Documentation is still in the works, I'll let you know when I have something ready for that. The code itself is documented fairly well too so you can look at that in the mean time.

The biggest thing for what you are asking is the definition of the descriptor. I'll see if I can get some of the raw USB data from the sniffer used to develop the code and post that up. That should help to visualize what is going on.

I am not familiar with the back end of Arduino and how the libraries compile together with the sketches, but all the modifications needed are going to be from these libraries. I will probably take this up after the season (but with Energia) for porting the CCS library to work in Energia.

Looking at the HID.c file from the Leonardo++ library it looks like they tried something like this, or at least have a 'raw hid' option.

Edit: I am told you can add CCS to normal eclipse as an add on, though I have never tried this.

Re: Using the TI LaunchPad from your KoP
 

I am contemplating using the TI MSP430 Launchpad for a project I have in mind. I would like to use this as an opportunity to learn to use TI microcontrollers. Please advise if the following is workable.

I would like to build a device to control the DC current to a load using a PWM output stage and monitor the load current and voltage using two of the ADC inputs. I would want to store the time-stamped data, most likely on an SD Card. The time-stamp does not have to be the actual time. The time since the start of the sequence would be sufficient. I was considering using a touch screen LCD for the user interface. I found the following Booster Packs on the 43oh web site. I am comfortable designing the switching circuitry myself since that is what I do for my day job.

http://forum.43oh.com/topic/1700-sdcard-booster-pack/

http://forum.43oh.com/topic/6149-24-...t-touch-panel/

Re: Using the TI LaunchPad from your KoP
 

Philso,
The Launchpad would be a perfect platform for what you're trying to do. The only issue you might run into using the booster packs you've found that I see is that they will both probably use the same SPI port. You would have to double check the pin-outs to ensure that the chip select lines are on different pins so you can mux them properly. I've worked with RobG and BlueHash from 43oh before though, and they are both great resources.

It looks like RobG made a booster pack that integrates the SD and LCD into a single design: https://www.tindie.com/products/RobG...d-card-socket/
You might want to take a look at that one to see if it will meet your requirements.

Another consideration to make is how accurate you need your current measurements. The Launchpad that we put in the KoP is the MSP430F5529, which has 12 bit SAR converters. We just recently launched the MSP432P401 LP which has 14bit converters that might give you some additional dynamic range/accuracy if needed. In addition, that board has the new MSP432 processor, which is a 48MHz 32bit Cortex M4F. The additional clock speed should also give you higher resolution PWMs (but I haven't looked into this specific feature).

Both of the Launchpads listed will also include an internal RTC capable of making accurate time stamps for your data logger. You can either set it to the current data/time, or just use it in free run mode as you described. I'm not personally familiar with designing and operating a DC current source via PWM, but I can ask around the 430 team to see if anyone has information I can share if that would help.

Re: Using the TI LaunchPad from your KoP
 

Thanks for your quick reply, Bart.

The MSP432P401 LP, with the 14-Bit ADC and PWM and internal RTC looks very attractive at just a few dollars more.

I had chosen the LCD with the touch screen to avoid needing to add a keyboard or keypad. I will check the chip select lines used by the two booster packs. I am guessing that if they conflict, I should be able to modify one of them to use a different GPIO pin.

I have done a bit of reading about the SD card booster pack and am a bit confused. It appears that the software currently can only read from the SC card and cannot write a file or it cannot create a file from scratch on the SD card. Is this true?

Re: Using the TI LaunchPad from your KoP
 

Good catch, I didn't even notice that the other one didn't have a touch screen.

One of our design partners also did an SD boosterpack which has a configurable CS pin location so you can avoid having to modify the hardware: http://boardzoo.com/index.php/booste...l#.VUt-PflVgZ4

Regarding the library, I know that PetitFS is a but limiting, but it was written to fit onto very small devices. The AdaFruit library should be compatible however: https://github.com/adafruit/SD
I got the examples to compile after removing the block of code where it wait's for the serial connection to enumerate on the Arduino, but I don't have the hardware on hand to test it. I'll try to snag a Boosterpack from someone around here to give it a whirl.

Re: Using the TI LaunchPad from your KoP
 

One of my coworkers suggested writing a Visual Basic program to run on a Windows computer to collect the data rather than saving the data onto an SD card. It would also eliminate the need to write so much low-level user interface software to run on the microprocessor. I am looking into either using a USB, WiFi or BlueTooth connection. Do you have any recommendations.

Having looked at the other LaunchPads, I am also considering using the LAUNCHXL-F28069M. It is similar to microcontrollers I have worked with on some of my boards at work (TMS28027 and TMS28335). I also like that the LAUNCHXL-F28069M can accommodate two Booster Packs and it's ability to perform math functions in one or two clock cycles.

Re: Using the TI LaunchPad from your KoP
 

If you're going to have a computer next to the data logger that's not a bad idea. Every LaunchPad has back channel serial that can be used to send data back to the computer pretty easily. C# is pretty easy to cobble some kind of interface together in, but you can also just use a serial terminal and copy the data to a txt or csv for processing from there. Some of the terminal program (I use RealTerm for this) can dump everything it receives to a txt natively, which might be sufficient.

If you're already familiar with the TMS2xxx devices, I would stick with that and use the back channel. If you do want to move to WiFi, the CC3200 LP can be used to stream data back over the network pretty easily, but you would have to setup a socket server or something on the PC side.