Tach question

[Stoli]

Sorry if this question has been answered elsewhere, but why is the output from the LM2907 (0-5v) fed into a A/D converter (3208) and not directly to an analog input on the arduino?

[designer2k2]

the A/D converters we use have much more precision than th arduino onboard A/D´s. Also this way we can keep as much as possible arduino pins free

[Stoli]

Thanks. I figured it was something like that. I have looked around your various sites and can't find any actual schematics of your project. Lots of pics of the boards but the only schematics I found were the tach and power supply. I would like to see how everything hooks up to the Arduino and can't really figure that out from the pcb pics. Did I miss something?

[designer2k2]

You can get all the PCB project files here: http://code.google.com/p/multidisplay/downloads/list

The Gerber PCB Files combined: http://code.google.com/p/multidisplay/d ... sV2_01.zip

MD01_V2 PCB & schematics: http://code.google.com/p/multidisplay/d ... _052.T3001
MD02 PCB & schematics: http://code.google.com/p/multidisplay/d ... 2_03.T3001
MD03 PCB & schematics: http://code.google.com/p/multidisplay/d ... 3_03.T3001

They are drawn in Target: http://www.ibfriedrich.com/

The schematics inside are not the pretiest, and with every evolution step it got worse

[Stoli]

Thanks! I saw those files but had no idea what program opened them. Now that I know they are the schematics, I'll go download Target and have a look. I'm doing a similar project for an old motorcycle that I am rebuilding and I think your tach circuit will work better than my original design (which used an opto-coupler between the points and an android pin configured as an interrupt). My plan is to feed all the sensor data into the Arduino and have it send the info to an Android tablet via Bluetooth. I have a dashboard app on the tablet that will display the info as gauges as well as log the data. Thanks again.