Quote Originally Posted by john swift View Post
The BOB you have linked to does not have the charge pump / watchdog circuit needed

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pin 17 just switches the relay on when the pin is taken high ( +5V )

one DIY circuit from Geckodrive.com

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John
Oh...my understanding was that the AXBB watched for the signal from the pc and then activates a chosen output for the charge pump. In my case it would be pin 17 controlled through the AXBB's 26pin idc to the bob which would then switch the onboard relay on to complete the circuit to power my safety relay for the drives.

Am I understanding it wrong? There should be no random outputs on the AXBBs port 3 lile would be on a pc's parallel port on start up or at least that's what I assumed.

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