Question about resistors.

[mistepien]

Hello,

great project. How do you know you need to use resistors in connections to most of db9 pins? Why do not you use diodes like i.e. 1N4148?

[doj]

there are 2 reasons:

• I had lots of resistors, but I don't have any diodes.
• I'm also not very good in electronics and wouldn't know if (or which kind of) diodes would be best for the output gates of an arduino chip and the input gates of the 6522.

I know that I should be able to simply hardwire both chips, but in case something goes wrong (soldering or my board schematics), I wouldn't fry the 6522 instantly if I put a resistor between the chips to limit the current flow.