lpcware

ISP behavior with P0.1 floating on boot?

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by Floyd42 on Sun Feb 02 07:39:53 MST 2014
What is the behavior with P0.1 floating on boot? The LPC810 user manual says that ISP mode is entered if it's LOW. But is does not say if an extern pull-up must be there or if the internal pull-up will be used. It seem is can be left floating and the user programm runs. That is also what they say at http://learn.adafruit.com/getting-started-with-the-lpc810/programming-the-lpc810-with-flash-magic.

For the default configuration the manual says about P0.1 (!ISP) and P0.5 (!Reset), that the internal pull-up resistor are enabled. Based on this, it appears to be save to leave them floating externally. Any official suggestion here?

Axel

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