View Full Version : Is there any way to invert PWM signals on BS2?

11-12-2009, 02:50 PM
I need to create a 4-channel PPM wave using inputs to the BS2. However they have to be "active low". That means the on is 0 and off is 1.

Is there any command/technique to invert the signal?

thank you.

Beau Schwabe
11-12-2009, 10:34 PM

I would say, just invert it in software, but the PWM function exits leaving the PIN LOW even if you force it to be a HIGH prior to the PWM command.

In this case I would use a simple transistor inverter or an IC such as a 74HC14 to provide my inversion.

Beau Schwabe (mailto:bschwabe@parallax.com)

IC Layout Engineer
Parallax, Inc.

11-18-2009, 03:38 PM
thanks. I got myself a 7404 NOT gate. HD74LS04P from hitachi.