UP Pins default Status

Carlo Alberto

Dear all,
From a preliminary analysis using the AeeonEAPI.lib seems that the pins have not a
common status at startup (see below). It is however unclear to me if the tested
status is a "Default" and will remain constant between reboots.

Having to develop interactive I/O devices attached to the UP board, the knowledge
about initial ports direction and status is crucial to me.

Is there anybody who can confirm the below status (I gather it at boot from UP board)
is guaranteed at boot? Does it change during the boot process? Do some input ports have
pull-up or pull-down resistors? Why having so many output ports at boot?

My OS platform is WIN10-64bits.
I have not found any technical information on this regards, nor similar forum discussion.

Any help would be welcome.
Kind regards
C.Alberto Avizzano


DETECTED SIGNAL STATUS LIST :
Signal 3V3 --> PIN1 Output Level High (meaningless)
Signal 5V0 --> PIN2 Output Level High (meaningless)
Signal P00 --> PIN3 Input Level High
Signal 5V0 --> PIN4 Output Level High (meaningless)
Signal P01 --> PIN5 Output Level High
Signal GND --> PIN6 Output Level High (meaningless)
Signal P02 --> PIN7 Output Level High
Signal P15 --> PIN8 Output Level High
Signal GND --> PIN9 Output Level High (meaningless)
Signal P16 --> PIN10 Input Level High
Signal P03 --> PIN11 Input Level High
Signal P17 --> PIN12 Output Level Low
Signal P04 --> PIN13 Output Level Low
Signal GND --> PIN14 Output Level High (meaningless)
Signal P05 --> PIN15 Output Level Low
Signal P18 --> PIN16 Output Level Low
Signal 3V3 --> PIN17 Output Level High (meaningless)
Signal P19 --> PIN18 Input Level High
Signal P06 --> PIN19 Input Level High
Signal GND --> PIN20 Output Level High (meaningless)
Signal P07 --> PIN21 Output Level High
Signal P20 --> PIN22 Output Level High
Signal P08 --> PIN23 Output Level High
Signal P21 --> PIN24 Output Level High
Signal GND --> PIN25 Output Level High (meaningless)
Signal P22 --> PIN26 Input Level High
Signal P09 --> PIN27 Input Level High
Signal P23 --> PIN28 Input Level High
Signal P10 --> PIN29 Output Level High
Signal GND --> PIN30 Output Level High (meaningless)
Signal P11 --> PIN31 Output Level High
Signal P24 --> PIN32 Output Level High
Signal P12 --> PIN33 Input Level High
Signal GND --> PIN34 Output Level High (meaningless)
Signal P13 --> PIN35 Input Level High
Signal P25 --> PIN36 Input Level High
Signal P14 --> PIN37 Output Level High
Signal P26 --> PIN38 Output Level High
Signal GND --> PIN39 Output Level High (meaningless)
Signal P27 --> PIN40 Output Level High