#linuxcnc-devel | Logs for 2016-04-15

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[07:11:49] <skunkworks> pcw_home, ran all night no issues 176us base thread
[11:12:12] <kwallace> Almost all of the bus switches I'm looking at have the output enable signal as active low. It seems more logical to have it active high. The goal is to not have the parallel port signals connected until the PC and software up and stable. Am I missing something? ( http://www.ti.com/lit/ds/symlink/sn74cbtd3861.pdf )
[11:51:37] <pcw_home> Active low is standard for enables (has been for 40 years or so)
[11:51:38] <pcw_home> The switch is also off when unpowered
[11:51:41] <CaptHindsight> kwallace: you can use a pullup resistor on the active low inputs
[11:54:38] <pcw_home> if you need active high, add a SS MOSFET driving the enable (with a pullup as CaptHindsight mentioned)