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Unread 14-01-2016, 07:51
Unsung FIRST Hero
Al Skierkiewicz Al Skierkiewicz is offline
Broadcast Eng/Chief Robot Inspector
AKA: Big Al WFFA 2005
FRC #0111 (WildStang)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 1996
Location: Wheeling, IL
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Re: Talon SRX CAN Issue?

To add to the list, terminations give the majority of CAN problems for all teams. The terminations when viewed as a load model for the transceiver chips terminates the bus in 60 ohms. This happens to be the approximate impedance of twisted pair #22 wire. When the terminations are not present as required, not only are reflections present, but the bus impedance rises to the point where the shunt capacitance starts playing havoc with rise times and noise.
Here is a TI paper on CAN...

Take a look at page 7 & 8.
https://www.google.com/url?sa=t&rct=...qLE8zQ&cad=rja
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Good Luck All. Learn something new, everyday!
Al
WB9UVJ
www.wildstang.org
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Storming the Tower since 1996.