opengauge development: gunio technical considerations

[dcb]

Originally Posted by larrydag

I quickly mocked up a possible pcb mock up for an arduino shield

Cool, having a shield as an option would only increase the appeal of the project. Not everyone likes my "sticks and mud" approach to assembling devices I'm sure

P.S. The serial board seems to work fine too (took 10 minutes to swap over):
P.P.S. I reoriented the buttons so that I am pushing down on them. I got tired of pushing my guino around the desk when I pressed a button

[MetroMPG]

Nice, Larrydag.

Sticks and mud rule, but that's neat too. FYI for any others who don't know what a "shield" is (I didn't, at first), it's a circuit board that plugs into the input/output pins on the *duino, on which you mount the additional electronic components your project needs.

(Did I get that right?)

[larrydag]

Metro, I'm new to arduino's too but as I've seen you got it correct.

[dcb]

FYI, I did a in car test last night:
http://forum.ecomodder.com/showthrea...5.html?p=24421

Results were promising.

[dcb]

The extra step of unplugging the 5v on the serial duino to program it, and the prospect of a lot of trial and error to get this working right, combined to motivate me to put the 4x20 lcd together with the usb duino.

The 4x20 lcd seems to be working without modification to the code (same pinout as 2x16 too):

Here is the backside with just buttons and lcd hooked up:

[larrydag]

This *duino is above the Opengauge price specs right now but if price is not an option it could be interesting. I can see possible in dash functionality with this microcontroller. I has all the features of an Arduino Diecimila for $45.

http://store.gravitech.us/arduino-nano1.html

[Funny]

[quote=dcb;24873]
The 4x20 lcd seems to be working without modification to the code (same pinout as 2x16 too):


I really would like to get started on one of these, even though I have a Scangauge and have a car that runs OBDII.
Do you think it's possible to program a Freeduino, along with an Elm 327 decoding IC, to work with OBDII? What about adding more EEPROM? Is that possible to allow for more code? Just giving ideas for MPGuino 2.0 (3.0?). I think it would be more aesthetically pleasing when using the 20 x 4 to add a space between the readouts and go out another decimal place, just a thought. By the way, this is an awesome project, you are an asset to us Ecomodders.

[dcb]

Originally Posted by Funny

I really would like to get started on one of these, even though I have a Scangauge and have a car that runs OBDII.
Do you think it's possible to program a Freeduino, along with an Elm 327 decoding IC, to work with OBDII? What about adding more EEPROM? Is that possible to allow for more code? Just giving ideas for MPGuino 2.0 (3.0?). I think it would be more aesthetically pleasing when using the 20 x 4 to add a space between the readouts and go out another decimal place, just a thought. By the way, this is an awesome project, you are an asset to us Ecomodders.

sure it is possible to interface with an elm chip, I've done it over a serial connection, but it could be integrated certainly. It is also possible to interface directly without elm, but it is a large amount of work and difficult to test properly, and will have lots of bugs. Even the elm folks don't claim 100% usefulness in all vehicles because the obd protocols are a pain in the butt.

I don't know where the 4x20 fits in the plan yet. I really like the small profile of the 2x16 (it is about half the size of a scangauge) so you can usually find a spot in front of your instrument cluster to put it without blocking something important. More data is good, but who wants to design and maintain two different versions of the code to support two different types of displays? And will that complicate things for the folks who are having difficulty with just one version of the code?

The good news is that the code is a bit Object Oriented, so that an advanced user can probably hijack an existing screen or add a new one and display any of the values for any of the trips with a few lcd.gotoXY and lcd.prints and pass in the trip values they want to display as they become available (i.e. instant.mph(),instant.rpm(), tank.dte(),instant.acceleration() ) . The LCD class in mpguino does support 4 lines/20 columns.

edit: the 4x20 may evolve into a configuration setting someday, along with customizable screens.

re: eeprom, it won't make the program space bigger but we could save more data (trips, fuel logs). But we haven't touched the 512 bytes of eprom that we have yet. It has room for 32 trips, or 85 fuel log entries, or some combination inbetween, plus need room for configuration data.

[jimboradley]

Did anyone else have trouble uploading code to their boards bought from nkcelectronics? I get LED13 blinking every second when I plug it in, but I don't seem to be able to upload to it. I get an error in the avrdude sync, and I'm not getting any help from the peeps at arduino.cc. Anyone else having problems?

[dcb]

Can you give some more details?
Is it a serial or USB board? Can you send a link to the product from the nkc site?

Is it just the assembled board or do you have the extra guino circuitry hooked up?

The once a second blink is a good sign, sounds like a connection problem.

[starquestPilot]

I had to load the USB drivers, then used comm port 13...

Mike

[larrydag]

jimboradley, it would also be helpful to know which operating system you are using. I can assist with Linux related issues since that is what I use.

[jimboradley]

Wow, thanks for the response. Shoulda done this first time around, but here's what I posted at the arduino site. I think it's got all the info I could scrounge up. Let me know if there's any other pertinent info I can gather. I'd really like to get this going.

Hi everyone. Like many people, it seems, I'm having trouble uploading sketches to my board. Here's what I'm using:
Windows XP SP2
Freeduino Serial v1.0 Diecimila compatible (from nkcelectronics.com)
a USB to serial converter cable set to
19200 baud
8 data bits
no parity
1 stsop bit
no flow control
using Arduino0011 (tried 009 also, but didn't work)

I've never been able to upload a sketch to my board. I tried all the tips in the troubleshooting section. Here is the output from when I try to load my sketch:

Stable Library
=========================================
Native lib Version = RXTX-2.1-7
Java lib Version = RXTX-2.1-7
Binary sketch size: 1096 bytes (of a 14336 byte maximum)
C:\Documents and Settings\OD\Desktop\arduino-0011\hardware/tools/avr/bin/avrdude
-CC:\Documents and Settings\OD\Desktop\arduino-0011\hardware/tools/avr/etc/avrd
ude.conf -v -v -v -v -pm168 -cstk500v1 -P\\.\COM1 -b19200 -D -Uflash:w:C:\Docume
nts and Settings\OD\Desktop\arduino-0011\examples\Digital\Blink\applet\Blink.hex
:i


avrdude: Version 5.4-arduino, compiled on Oct 11 2007 at 19:12:32
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/

System wide configuration file is "C:\Documents and Settings\OD\Desktop
\arduino-0011\hardware/tools/avr/etc/avrdude.conf"

Using Port : \\.\COM1
Using Programmer : stk500v1
Overriding Baud Rate : 19200
avrdude: ser_open(): setting dtr
avrdude: Send: 0 [30] [20]
avrdude: Send: 0 [30] [20]
avrdude: Send: 0 [30] [20]
avrdude: Recv:
avrdude: stk500_getsync(): not in sync: resp=0x00
avrdude: Send: Q [51] [20]
avrdude: Recv:
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

avrdude done. Thank you.

I've tried wiring my serial connector up to itself, and it echoes the characters I transmit from the serial monitor perfectly, so I don't think my cable is a problem. I also tried tieing my rx and tx pins together and transmitting stuff using the serial monitor. The stuff that comes back on the serial monitor is usually slightly garbled, sometimes every character comes back wrong. I transmitted the English alphabet several times and maybe one time in 5 it came back with all 26 letters the same. Not sure if this behavior is expected or not.

I do get LED 13 to flash when I reset, but it doesn't look like a triple flash. Seems like it just flashes every one second constantly. When I try to upload something, it looks like the LED flashes an extra time or two when avrdude first does ser_open() and stk500_getsync(), but keeps flashing every one second.

Anyone have any insight into what I'm doing wrong? Thanks in advance.

[dcb]

Originally Posted by jimboradley

...a USB to serial converter cable..

Has anyone else here tried this configuration?

[ttoyoda]

From reading some FAQs I was under the impression that high port numbers could be a problem and that the baud rate was 9600 in some cases. I have no actual experience with the board so I probably do not know what I am talking about. DO NOT take my word for it.

[jimboradley]

Well, I'm set up on COM1, I think, so the port number shouldn't be a problem. I thought I tried playing around with the baud rate, but I can try that again, when I get home.

[dcb]

what com ports show up when you go to:
tools->serial port

[jimboradley]

I'm at work, now, so I can't check for sure, but I think it's COM1 and COM4

[jimboradley]

Yep, just checked. COM1 and COM4 show up.

[dcb]

if you unplug the usb part of the cable and restart arduino, does the list change?

do you have a standard serial cable handy? I'm not convinced the usb->serial adapter is recognized.

Also, if you can jumper power to the duino or re-orient the power plug, you can plug it straight into the computer serial port (if you don't have a cable):


power plug rotated upward: