PDA

View Full Version : Need help RCtime ? Tracy Allen or anyone can help.



Tomvn
11-30-2009, 12:44 AM
i have the boebot use 12v battery and convert to 8Volt to connect to BS2· so i use RCtime to measurement the volt and i want· debug window display exactly· my 12V battery ,so could i hook direct Gnd to -12V and plus terminal to +12V and signal pin to BS2 pin to calcular axactly 12v battery
so that will hurt the BS2 stamp pin or not?

Tracy Allen
11-30-2009, 12:47 AM
Sure....
Try this www.emesys.com/BS2rct.htm#B_voltage (http://www.emesys.com/BS2rct.htm#B_voltage)

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Tracy Allen
www.emesystems.com (http://www.emesystems.com)

Tomvn
11-30-2009, 12:56 AM
Hi Tracy
i have make exactly what you are show on your website and just make sure i can connect direct to 12v battery without to 8v convert from stamp and the signal pin to BS2 stamp pin ? because i read somewhere on net someone said that will hurt the stamp pin if i use 12v battery for Bs2 chip .
If you say sure i will try it,
Thank you very much.

Tracy Allen
11-30-2009, 01:27 AM
Hi Tomrobo,

If you make the circuit as shown with the 681 kOhm resistor between the 12 volts and the input, it limits the current to less than 20 microAmps. That is a safe level for the protection diodes inside the Stamp. There is also a 470 Ohm resistor for additional safety.

I may not be understanding exactly what you are trying to do and how the 8 volts fits into the picture. The Stamp module Vin pin is the only one that accept power supply voltages greater than 5 volts. Never apply 12 volts or 8 volts directly to a Stamp input pin. However, if there is a high value resistor in series to limit the current, it is okay, because the Stamp has internal diodes that can divert the current of 1mA or so into the power supply or to ground. Always be careful when wiring it up. No mistakes!

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Tracy Allen
www.emesystems.com (http://www.emesystems.com)

Tomvn
11-30-2009, 03:24 AM
Hi Tracy
i mean i use 12v battery then convert to 8V then connect to edu parallax board not to input pin and the Vin pin is 8V
thanks.

Post Edited (Tomvn) : 11/30/2009 12:49:07 PM GMT