Basic question about components and resistors

Forum 2005-2010 (read only) Hardware Interfacing
1

In looking at sample schematics, there is always? A resistor between power and component. how do I know when to use a resistor and of what size?

2

They are probably pullup resistors.
See http://www.seattlerobotics.org/encoder/mar97/basics.html
for info and V=IR formula in use. Engrave V=IR on your skull OK? :slight_smile:

3

http://www.ikalogic.com/beg_1_res_v_c.php