Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision | Next revision Both sides next revision | ||
|
xro:beaglebone [2015-12-09 00:21] xro |
xro:beaglebone [2015-12-09 00:29] xro |
||
|---|---|---|---|
| Line 49: | Line 49: | ||
| ==== Transient State of pins during startup ==== | ==== Transient State of pins during startup ==== | ||
| + | |||
| + | Basically, until the Device-Tree-Overlays are loaded, the Beageblone-Blacks gpio pins are in ''INPUT'' mode and sometimes, during bootup, may switch devices your relays and other stuff that depends on your pins being configured for ''OUTPUT'' at level 0, when powering up. | ||
| + | |||
| + | There are two possible solution that I know of. | ||
| + | - Don't power up your external gpio-controlled hardware before the BeagleBoneBlack has booted | ||
| + | - Guard your GPIO Pins with some Peripheral-Buffer IC's that need an **EN**able signal. | ||
| + | |||
| + | In both cases, you still need a pin to connect the EN signal or power-relay for our peripherals, | ||
| + | a PIN that you can trust to stay in a certain state during and after bootup. | ||
realraum Graz, Brockmanngasse 15, 8010 Graz, realraum - Verein für Technik in Kultur und Gesellschaft