embeded/raspberry pi2018. 2. 19. 14:09

레트로 파이 돌리다 보니

우측에 번개모양 아이콘이 떠서 찾아 보니 음.. 전력 부족이면 뜨는건가?


배포판 버전 올라가면서 단순하게 무지개 모양(쉐이더?) 에서 아이콘을 변경한건가..

아무튼 해당 부분 표현하는거 어디서 하는지 찾아 봐야겠다.

(보이는게 신경 쓰이기도 하고)


음.. rpi 2B에서 잘못 출력하는건가?

그래도 아이패드용 어댑터에서 5V는 정상적으로 나올텐데 4.63V/+-5% 보다 낮으면 띄운다니.. 머지?

Undervoltage warning

If the power supply to the Raspberry Pi drops below 4.63V (+/-5%), the following icon is displayed. 

[링크 : https://www.raspberrypi.org/documentation/configuration/warning-icons.md]

   [링크 : https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=177477]


아무튼 정석은 어댑터 교체이고 차선책(?)으로는 설정에서 해당 출력을 하지 않도록 해버림

$ sudo nano /boot/config.txt

# Disable under-voltage warning

avoid_warnings=1 

[링크 : https://scribles.net/lightning-bolt-under-voltage-warning-on-raspberry-pi/]

[링크 : https://www.raspberrypi.org/documentation/configuration/config-txt/misc.md]

---

Power: Ensure you have a good power supply which can steadily supply at least 2A at 5V. Many power supplies sag voltage and current under maximum load. If you see a lightning bolt icon or rainbow square in the top right corner during regular operation, this is the under-voltage warning and you are not supplying enough power. If you have USB devices plugged into the USB ports, considering getting a good powered USB hub to reduce power draw on the Pi. 

[링크 : https://www.reddit.com/r/RetroPie/wiki/faq]


aha so power brownout

Probably, although I haven't done an rpi-update and looked myself, and the commit doesn't say.

It would be the most logical one out of under-voltage and over-temp (yellow or red). 

[링크 : https://www.raspberrypi.org/forums/viewtopic.php?t=159679]


Finally on the subject of icons, in the past if your Pi was working particularly hard, you might have noticed some yellow and red squares appearing in the top-right corner of the screen, which were indications of overtemperature or undervoltage. These have now been replaced with some new symbols that make it a bit more obvious what’s actually happening; there’s a lightning bolt for undervoltage, and a thermometer for overtemperature. 

[링크 : https://www.raspberrypi.org/blog/introducing-pixel]

    [링크 : https://raspberrypi.stackexchange.com/questions/57963/what-does-the-lightning-bolt-mean/57998]

[링크 : https://www.element14.com/.../pi3-shows-yellow-lightning-bolt-with-official-power-supply...]


+

어떤 레이어에서 출력하나 궁금하네..

단순한(?) OSD 레이어로 출력하는걸려나?


pi@raspberrypi:~ $ vcgencmd get_throttled

throttled=0x50000 

[링크 : https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=147781&start=50#p972790]


+

모니터 없이 써서 내가 몰랐던 걸려나.. 꽤 오래전 부터 있었네..

(생각해보니까 openELEC에서 계속 뜨는데 걍 뜨나보네.. 하고 무시하고 살았....)

pi@raspberrypi:~ $ sudo apt-get install stress stress-ng

pi@raspberrypi:~ $ stress-ng --cpu 4 --io 1 --vm 1 --vm-bytes 128M --timeout 10s --verbose 

[링크 : http://www.solanara.net/solanara/raspberry#head_raspberry_tip_warnicon]



+

커널받아서 검색중

Search "avoid_warnings" (1 hit in 1 file)

  D:\Download\linux-rpi-4.9.y\drivers\gpu\drm\vc4\Kconfig (1 hit)


config DRM_VC4

tristate "Broadcom VC4 Graphics"

depends on ARCH_BCM2835 || COMPILE_TEST

depends on DRM

depends on SND && SND_SOC

depends on COMMON_CLK

select DRM_KMS_HELPER

select DRM_KMS_CMA_HELPER

select DRM_GEM_CMA_HELPER

select DRM_PANEL

select SND_PCM

select SND_PCM_ELD

select SND_SOC_GENERIC_DMAENGINE_PCM

select DRM_MIPI_DSI

help

  Choose this option if you have a system that has a Broadcom

  VC4 GPU, such as the Raspberry Pi or other BCM2708/BCM2835.


  This driver requires that "avoid_warnings=2" be present in

  the config.txt for the firmware, to keep it from smashing

  our display setup. 



+

두개가 동일한 회로인진 모르겠지만.. 일단 Schematic 상에 2B V1.2 에는 

APX803 칩이 내장되어서 무언가 하긴 하는 듯?

[링크 : https://www.raspberrypi.org/.../schematics/Raspberry-Pi-2B-V1.2-Schematics.pdf]


[링크 : https://www.raspberrypi.org/.../schematics/Raspberry-Pi-3B-V1.2-Schematics.pdf]


외형상으로는 걍.. 3핀 SOT로 레귤레이터인가 보다.. 하고 넘어갔던 녀석중에 하나 인 듯


APX803-46의 리셋 경계값이 4.56V(Min) 4.63V(Typical) 4.70V(Max)

[링크 : http://www.mouser.com/ds/2/115/APX803_D-86185.pdf]


+

커널이 아닌 VideoCore IV Firmware에서 관할하기에

라즈베리 커널에서 이미지나 코드 관련해서 뒤져도 해당 아이콘의 이미지가 안나오는 것으로 예상된다

(즉, 내가 찾기 귀찮으니 이정도로 끝내겠다? ㅋㅋㅋ)

[링크 : https://www.raspberrypi.org/forums/viewtopic.php?t=158777[]



+

끝이 아니라니..

이 놈이.. 온도 관련해서 센서 대신 사용하는 놈인가?

주변 온도에 따라 저항값이 달라지는데 이걸 사용하기에는 저항값 변화가 너무 적고..

용도가 머지?


N-CHANNEL ENHANCEMENT MODE MOSFET 

[링크 : https://www.diodes.com/assets/Datasheets/ds31783.pdf]


+

B+ 에서부터 깜박인다고 하는데 깜박이진 않고, 해당 마크에 대한 이야기가 없네.. 머지?

Red power LED is blinking

A blinking red power LED indicates problems with the power supply. On model A and B, it is hard-wired to the 3.3V power supply rail. If it is blinking, as one user has reported[1] it means the 5V power supply is dropping out. Use a different power supply.

On model B+ (and presumably also the A+), the circuit has been improved to give a much more reliable warning of poor power quality. The red power LED is wired to an APX803 supervisor[2] which kicks in when the 5V power supply drops below 4.63V[3]. If it does, the LED will blink. Check your connections, cable, and power supply.

[링크 : https://elinux.org/R-Pi_Troubleshooting#Red_power_LED_is_blinking]


그나저나.. 아이패드 충전기 5V 1A이고 USB 길이가 일어야 30cm도 안될 녀석인데

그 거리에 전압강하가 될리는 없고.. 실측하기도 빡센데 흐음.. 우짜지?

The Raspberry Pi 2 has a 2.2 amp polyfuse which limits the power which may be supplied via the microUSB socket. This is more than enough to power the Pi and the USB sockets.

Initially the USB sockets can only draw 600 mA. At worst this leaves 1.6 amps for the Pi2 and anything connected to the gpios.

By changing a setting after boot software can configure the USB sockets to draw up to 1.2 amps. At worst this leaves 1 amp for the Pi2 and anything connected to the gpios.

You haven't mentioned connecting anything to the gpios or the USB.

The only meaning to the rainbow square in the top right of the screen is that the 5V line has dropped beneath 4.65V.

If you trust the power supply to be accurate the other cause of low voltage is thin wires in the microUSB cable. 

[링크 : https://raspberrypi.stackexchange.com/questions/34305/undervoltage-rainbow-despite-good-power-supply]

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  1. 123

    번개모양 아이콘이 도대체 정체가 뭔지 알고싶네요.. ㅠ

    2018.03.14 22:52 [ ADDR : EDIT/ DEL : REPLY ]
    • rpi3 에서는 5V 가 들어와야 하는데 4.6V 이하일 경우에는 저전력이 들어오고 있다고 경고 주는 건데
      rpi2b에서도 정상작동하는진 모르겠습니다.
      테스터로 찍어봐도 5V 로 나오는데 번개가 뜨더라구요

      2018.03.15 05:55 신고 [ ADDR : EDIT/ DEL ]