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Unread 11-01-2010, 18:00
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Re: Serial to CAN Gateway in new Black Jaguars?

Quote:
Originally Posted by ajlapp View Post
I previously recall someone mentioning that both pwm an CAN cables had to be connected to a jaguar for a heartbeat message. It sounds to me like this isn't the case.
The connection of both CAN cables and PWM cables is only necessary if the CAN bus is being spoken to through an "untrusted" interface -- one for which a "trusted" driver is not being used. The definition of "trusted" here is more-or-less a driver that is certain to be obeying the enable/disable signals and can inform the Jags that it is doing so. If the Jags are not informed that the CAN messages can be "trusted" then it will require the PWM heartbeat.

At the moment, the only "trusted" driver that I am aware of is that which uses the serial port on the cRIO and assumes it is connected to a black Jag as a serial->CAN bridge. See http://firstforge.wpi.edu/sf/frs/do/....canjaguar/frs

All that said, the rule as written seems to deny the use of "untrusted" CAN. I obviously do not know if that was intentional.