VEMS Community Forum

Technical => Wiring & Sensors => Topic started by: mattias on September 02, 2015, 10:37:38 pm

Title: Adding third trigger input ( SDA )
Post by: mattias on September 02, 2015, 10:37:38 pm

Hi!

Was wondering how to interpret the text below from this page : http://vems.hu/vt/help/v3/v3_camshaft_angle_control.html

Quote

The third trigger is a processor input pin without any protection.
To set it up, use Pull-up resistor, a 10k protection resistor, and protection Diode, and a 22nF capacitor (min 10nF) between processor pin and GND.

Firstly : The SDA input already has 4.96 Volts on it with nothing connected. Does it need a stronger pull-up? What size resistor must I add towards +5V ?
No work bench to test the strength of the pull-up, was hoping for quick/easy answers.

Secondly : I assume the 10k protection resistor connects to SDA pin and sits in series with diode (1N4007, stripe towards +5V ?) ?