Olimex Support Forum

OLinuXino Android / Linux boards and System On Modules => A20 => Topic started by: tejas.s on March 16, 2018, 03:52:10 AM

Title: Lime2-e4GB disable Auto-boot on AC-power
Post by: tejas.s on March 16, 2018, 03:52:10 AM
Hi,

I want to disable the auto-boot of the Lime2-emmc board when the AC power is applied and control the turn-ON and
turn-OFF using power-button only, there is no battery connected to the board. What are ways in which this can be achieved?

I am planning to make changes to the u-boot\board\sunxi\board.c such that I wait inside a while loop till there is IRQ for short press of the power button(PEK). I will update after I try this. Please let know if there are any other ways to achieve this.
Title: Re: Lime2-e4GB disable Auto-boot on AC-power
Post by: LubOlimex on March 16, 2018, 10:55:44 AM
Try to change power_start to 0 in script.bin

Read about how you can edit script.bin here: https://www.olimex.com/wiki/How_to_edit_board_configurations_and_definitions_in_the_official_Debian_Linux

If it doesn't work, you might need to edit the u-boot as explained in this post:

https://www.olimex.com/forum/index.php?topic=4207.msg19301#msg19301

Title: Re: Lime2-e4GB disable Auto-boot on AC-power
Post by: tejas.s on March 16, 2018, 12:43:54 PM
Quote from: LubOlimex on March 16, 2018, 10:55:44 AM
Try to change power_start to 0 in script.bin

I have already tried setting power_start to 0. This doesn't change the boot-up behavior of the board.
Also, the fex-guide doesn't explain the significance of setting power_start to 0.

Quote from: LubOlimex on March 16, 2018, 10:55:44 AM
If it doesn't work, you might need to edit the u-boot as explained in this post:

I cant implement this as I am not using the board with battery power supply. I do want to power on with the 5V source but only when the PWR button is pressed.