MPGuino shield: Fork? V2?

[firehawk618]

Thank you so much! That part did have me slightly confused. The best I could figure is that was your LED display?

Anyways thanks for actually responding to a thread you started YEARS ago!

I did see your last activity was ~3 years ago before I posted here so I was quite shocked when you replied.

I will assemble the hardware tomorrow and commence playing!

[bobski]

Turns out the email reply notifications still work.
And yes, the LED display is over I2C.

[firehawk618]

Was your last revision working to your satisfaction?

Were you able to get the large numerical readout going?

If you don't want to keep replying I totally understand, once I have a base running I can muck around and try to figure that stuff out.

[bobski]

Originally Posted by firehawk618

Was your last revision working to your satisfaction?

Umm... no? It's functional, but very light on features.

Originally Posted by firehawk618

Were you able to get the large numerical readout going?

You mean like double-height characters? No, I haven't played with that. As I understand it, it's a matter of sending custom characters to the display panel and assembling 4 of them on the screen to get the desired number. A dogm128 might be easier. ^_^

[Theitguy]

Originally Posted by bobski

Mmmkay... Current hardware:

This may be a stupid question, but how would it affect the injector circuit if i used a different opocoupler? say a 4N28/4N25?

And Bobski, thanks for all your work taking this back to arduino! i have been keen on this project for a while but stuck in the mud until i stumbled upon this revision!

Much appreciated
Mitch

[Theitguy]

Also, i am having trouble finding the parameter in code No#3 that sets the Vss pin no#... i need to set it as pin 2 as my lcd shield uses pin 3....
thanks
Mitch

[bobski]

Originally Posted by Theitguy

how would it affect the injector circuit if i used a different opocoupler? say a 4N28/4N25?

Should work. The trouble I ran across with the optocoupler was that it distorted the measured pulse length. The rise and fall times of the opto's output are different, and depend on the value of the pull-up resistor (10k-ohm on my diagram). If you have a reference signal, you could measure the distortion and subtract it in software.

[bobski]

Originally Posted by Theitguy

Also, i am having trouble finding the parameter in code No#3 that sets the Vss pin no#

It's in void setup():

attachInterrupt(1,basicVssInterrupt,RISING);

Unfortunately it's hardware limited to certain pins.
Arduino - AttachInterrupt
Move the pin on your shield?

[Theitguy]

Hey, thanks for the replies! it really is much appreciated!

I will look into moving the pin on the shield, it really is a pain in the ass that they use that pin!

If it proves to be to hard to move the pin, you meantioned that the pins are hardware limited, is it because they can read pulses at a higher speed? if so ill do some research on which other pins also have this ability.. maybe :P
also, in regards to the code:

attachInterrupt(1,basicVssInterrupt,RISING);

The figure "1" sets the pin as 3?

Sorry for all my ignorance and stupid questions, im still getting the hang of all this arduino rubbish!

Cheers
Mitch

[bobski]

Originally Posted by Theitguy

is it because they can read pulses at a higher speed? if so ill do some research on which other pins also have this ability

With greater precision, yes. Check out the attachInterrupt link i posted above. In short, interrupts let the software immediately stop what it's doing, deal with the interrupt routine and then return to what it was working on. In this case, basicVssInterrupt figures out the time between VSS pulses (vehicle speed) and increments the VSS pulse count (odometer).

Originally Posted by Theitguy

attachInterrupt(1,basicVssInterrupt,RISING);
The figure "1" sets the pin as 3?

It depends which board you're using, but that's the gist of it, yes. Again, check the link.