BPI-R2 boot / power suppy

Banana Pi Router design
82

The new MB is rev 1.2

83

you can try my debian (https://drive.google.com/open?id=1oP7jy1KrrIOifvImo2nQ59wx3_9hHkgk 4.14.80) burn to mmcblk1+ preloader to boot0 but you need to change in uenv.txt partition 1:1 to 0:1 and root to /dev/mmcblk1p2 (should be mmcblk0p2) and in root-partition/etc/fstab (mountpoint for /) also to /dev/mmcblk1p2

84

New few test. Slackarm updated to the fresh current version, kernel the same: 4.19.16 and two BPI-R2 MB: 1st rev 1.1 with soldered power-switch and second rev 1.2 without soldered power-switch.

On both now I havenā€™t kernel panic but on the 1st a have:

INIT: Switching to runlevel: 0
INIT: Sending proceRunning shutdown script /etc/rc.d/rc.0:
INIT: version 2.93 reloading
Saving system time to the hardware clock (localtime).
Stopping system message bus...
Unmounting remote filesystems:
Stopping udevd
Sending all processes the SIGTERM signal.
Sending all processes the SIGKILL signal.
Saving random seed from /dev/urandom in /etc/random-seed.
Turning off swap.
Unmounting local file systems:
/sys                     : ignored
/proc                    : ignored
/                        : successfully unmounted
Remounting root filesystem read-only:
mount: /dev/mmcblk0p2 mounted on /.
[   60.111412] reboot: Power down

and MB no powering off - still on.

The 2nd powered off correctly after poweroff command.

If something from mmcblk1boot0 (eMMC boot part) can have impact on this situation on 1st BPI-R2?

I done one more test with 2nd MB (BPI-R2 rev v1.2) without soldered power-switch and not touched eMMC. But, to UP it automatically when power back I connected 5V to otg. And, on poweroff command I have the same result as on the 1st MB with soldered power-switch. MB was not powered off but keep stay on [.................] reboot: Power down message :slight_smile:

Result are the same with and without acpid.

85

Thank you for your tests,but currently i have no idea how to ā€œfixā€ it. Maybe itā€™s impossible to power it off if it is externally ā€œforcedā€ to power-on (with bridged power-switch/otg-power).

How do you want to power it on if you have it powered off (disabled power-switch)? I think there can be no solution.

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Yes @frank-w, you have right, it is true. Iā€™m awareness about this circle :slight_smile:

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Very easy Arduino project solved the problem definetly (Arduino Mini 3.3V):

IMG_20251112_115202
IMG_20251112_1152021277Ɨ1833 270 KB

int pin = 13; // PIN NUMBER

void setup() {
  // put your setup code here, to run once:
  pinMode(pin, OUTPUT);
  digitalWrite(pin, LOW); // Make signal LOW
  delay(10000);            // wait 10 sec
  digitalWrite(pin, HIGH);  // Make signal HIGH
}

void loop() {
  // put your main code here, to run repeatedly:

}

Now Arduino switch on the power button for 10 sec. Regards, Radek

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Nice project. Guess you could even use an attiny85 for that.

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Be careful with power levelā€¦arduino is most 5v and bpi-boards are mostly 3.3v

Afaik also a FET would be enough with some self holding circuit (capacitor for 10s).

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I measured the voltage on the standard Power button and itā€™s 3.8V. So everything should be fine. But for security reason better will be probably Arduino 3.3V.

91

Ok, i verified documentation. MT6323LGA (Power Control module) can be powered between 3,4 - 4,5 Volts. Logical HIGH signal from Arduino 5V can be too much for MT6323LGA.

I replaced Arduino 5V with Arduino 3.3V and itā€™s working fine also. @frank-w thank you for your suggestion, now all is working without problems and is safe. Regards, Radek.

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