MPGuino with large screen?

[Nevyn]

I know the standard size is a 16x2 LCD, and that's great. Would it be easy to just swap to something like a 20x4 LCD, without any major software rewrite on my part, or would it take a lot of changes?

Secondly, would it be possible to use the "Big Number" instant MPG readout on a second "remote display?" I'd love to have my screen up front, and a BIG one in the back window that other drivers could see. Even if it was just a clone of whatever was being displayed for the driver it would be neat.

I'm not the best code monkey out there (I'm a computer/electronics hardware technician, not a programmer), but I have a little bit of coding experience and I'm not afraid to get dirty.

Thanks for any insight you can provide! I'm hoping to be able to get to 35 MPG with this beast....

[cmags]

I think its been mentioned that the best way to have two screens populating data on these things is to build two and tie them to the same inputs.

In theory, with one more pin to switch power between the two LCDs, or the enable, you could add code to send one screen full of data with the enable on for one LCD, then another screen with the other enable on. The LCD holds its data displayed until another enable pulse goes in so while updating one, the other wouldn't change display. I dunno if there's enough codespace left for that though.

[i_am_socket]

The newest version of the code already has serial output for remote displays or attachment to other devices, so it should be relatively easy to do.

Relative to what, I couldn't tell you

[Nevyn]

Originally Posted by i_am_socket

The newest version of the code already has serial output for remote displays or attachment to other devices, so it should be relatively easy to do.

Relative to what, I couldn't tell you

Hmm....I was thinking that the data out would really only be useful on a PC, but I guess you could feed it into a 2nd MPGuino with different code that is set to pick the data from serial input and not from the engine pins?

[cmags]

Well, if you're going to use a second MPGuino, then you might as well hook it up to the same inputs, rather than re-invent both sets of code, have two, each with whatever display you want on it.

[Nevyn]

It may actually be easier to re-invent the wheel, or maybe I'm looking at a different project. Get one of those (relatively) big LED monochrome displays, and set it to say


"I'm getting XX.X MPG right now, how about you?"


Where it grabs the instant MPG from the MPGuino and displays it in the middle of the string. I'd mount it in the bottom of the back window.

Could also wire an input for brake lights and have it act as a 4th brake light too.

[i_am_socket]

From the latest on the Wiki:

10/01/2008 updates for v0.74

added a small serial transmitter function. The guino now outputs the following data over the serial port at 9600 baud every half second: instantmpg, instantmph, instant.injHius, instant.injPulses, instant.vssPulses

So "realtime" laptop/cellphone integration should be a snap if your guino has a usb/rs232 connection or you can build one and you can gather the data on the laptop/cellphone. This also has applications for remote displays.

I also added a #define usedefaults so that you can build the guino without a lcd if you intend to only use it with a laptop/cellphone. It will simply skip the setup screen/loading of eprom values.

Since all the interesting data is already going over the serial port now, I removed the debug ifdef branching.

At that point, if you know how to build something to pick up serial data and only display the MPG, it should be simpler and cheaper than a full second MPGuino. That's a big "if" though.

[UK Mini]

Originally Posted by i_am_socket

From the latest on the Wiki:


At that point, if you know how to build something to pick up serial data and only display the MPG, it should be simpler and cheaper than a full second MPGuino. That's a big "if" though.

SparkFun Electronics - Breakout Board for MAX7456 On Screen Display will superimpose spi data over a composite video signal. Not exactly HUD but if the video is from a camera (rear view?) on your car...

Another idea could be a persistence of view projector to get a much brighter image to reflect off the screen

[dcb]

that would be interesting to combine with a camera signal.

[enuro12]

Originally Posted by Nevyn

I know the standard size is a 16x2 LCD, and that's great. Would it be easy to just swap to something like a 20x4 LCD,

How about this
20x4 HD44780 Blue LCD

Same controller on the LCD as the regular one. Just change code to do 4 lines instead of 2

They're all over ebay.