Official MPGuino preassembled now available

[drimportracing]

I finally donated after a year of dragging my feet. I have great expectations for the mpguino. I'm at a 43.1mpg average for pizza delivery driving for the last 15 months of hypermiling. I've had a few 47+ tanks but they are hard to come by. Wish me luck on this much needed mod. - Dale

[mluckham]

Originally Posted by dcb

it is socketed, comes with a 168. Retrofitting a 328 and custom programing are sort of an advanced topic, doable but not something I care to mess with right now.

I ordered your MPGuino and got it within a few days - nice.

Replacing your 168 chip with a 328P from Adafruit plus my metric software worked fine. In fact I can swap chips between yours and my spiffie.org MPGuino without problems. I was a bit surprised that yours doesn't have a USB port though ...

[dcb]

re: usb, you have to get into surface mount stuff for that, and extra costs, and I ditched the bootloader for reliability and space anyway. It is all ISP now. I've gotten completely away from the arduino model for more practical reasons. The tx pin is still sending though, 9600 n81.

[mluckham]

It's all good

Thanks for the info re: TX pin.

[dcb]

more comm info, not a lot of folks use/need it, but if you are interested:

for usb connections: FT232RL based (needs drivers for windows)
SparkFun Electronics - FTDI Basic Breakout - 5V $14


for rs232 serial port:
SparkFun Electronics - RS232 Shifter Board Kit $7

The TX pin is hard to get to, what I did to avoid soldering on the IC was to hammer a small piece of solid copper wire flat and slide/jam it in the socket along with the tx pin.

but ground and 5v should be easy enough to tap with a blob of solder. You probably don't want to connect to 5v with the usb adapter in the car.

Every 1/2 second it sends:
//send out instantmpg * 1000, instantmph * 1000, the injector/vss raw data
simpletx(format(instantmpg()));
simpletx(",");
simpletx(format(instantmph()));
simpletx(",");
simpletx(format(instant.injHius*1000));
simpletx(",");
simpletx(format(instant.injPulses*1000));
simpletx(",");
simpletx(format(instant.vssPulses*1000));
simpletx("\n");

[AlainB7]

Thanks mluckham for te Metric MPGuino!

Just finish installing it into the VX. I will post picture of installation. I find a realy nice place to fit it in!

[mluckham]

Originally Posted by dcb

You probably don't want to connect to 5v with the usb adapter in the car.

I have the Spiffie.org MPGuino, which has a USB connector ... I've been collecting the printf output with a laptop.

I've been looking for an Arduino USB Host project - thinking to be able to connect two Arduino's together - one with the standard USB client plug, and the other datalogging onto a memory card. Ideal would be an Arduino with USB Client/Host mode selectable with a switch, then logging could be direct to a USB memory stick

[dcb]

ok, have fun with that Sounds like its time for a new thread.

[evgrready]

Technical Question about VSS

I have a mechanical speedometer. Do you know of any kind of adapter to attach in line with your mechanical speedo cable and also would give you a VSS signal?
I have a 91 VW GTI with Digifant Injection System (Gang Injection, Not Sequential)
I did my Donation and I just have extra questions.
Please Advice.
Thanks a lot.
Edgar

[dcb]

If your gti has cruise control, it probably has a vss already, finding it in the schematic and tapping it in the car is the biggest challenge.

if no vss then you need to install something if you want the guino to track distance. The simplest conceptually might be to take a bicycle computer and strap the magnet to an axle shaft (the inboard most end would be best) and make a bracket to hold the switch near it, then wire it up to switch 12v and feed it to the guino.

the reed switches are a little noisy however, so you would be better served with a hall effect switch, but I don't have a circuit diagram handy.

opto might be another option.