傳說在機械化的黃金時代，流傳著一則故事︰
那時每一根小『螺絲釘』和小『螺絲帽』都是獨特的，不要說從這個工廠到那個工廠，就算在同一個工廠內，它們也都各有各的不同。只有那些沒有螺絲帽可以匹配的螺絲釘或沒有螺絲釘可以匹配的螺絲帽，才會被歸類成不好的。就這樣過了很多年，直到有一天艾索 ISO 出現了，推動『標準化』運動，自此一切都改變了 …。傳聞，最後一根獨特的小螺絲釘說︰『艾索，你這個老狐狸！…』。終究這些風塵往事早已被世人遺忘。
─── 《瑪利歐的水管 PIPE》
或許因為曾經寫過
‧W!O+ 的《小伶鼬工坊演義》︰通往樹莓派 3 之 HEARSAY 電源
……
文本，日前朋友問到︰嘗見樹莓派
Under-voltage detected! (0x00050005) … how to disable?
核心訊息耶？
因不知也；故谷歌
Under-voltage detected! (0x00050005) … how to disable?
I developed a digital signage solution at the Raspberry Pi platform. Since I got a Raspberry Pi 3B+ I updated to Raspbian Stretch and get now both, the yellow lightning and the message on the screen.
Is there any chance to turn this message off? I want keep the yellow lightning, but the message completely destroys the clean look of the UI, because I did not find out how to hide it. It overrides the frame buffer.
This really makes the Raspbian worthless for professional solutions. 
………
看看所言何事喔？一時訝異
其間議論紛紛者，到底在談『系統品質』還是『訊息管控』呢？ ？
恰逢說『戴維寧定理』之際，激發好奇！！或當與時並進呦？？
故而查找資料
Power Management Chip on RPI3B+
Power Management Chip on RPI3B+
Hey everyone,
Was curious about what functions that Power Management Chip does on the Raspberry Pi 3B+, I know it says it allows for better Signal transmission for power, but what else does it help Manage. If thats all it actually does, how does it do it compared to just using the fuses/resistors that was used previously?
Does the OS/Kernel have access to the PMC or does it do its own thing?
Thanks!
Re: Power Management Chip on RPI3B+
TehWoomiestRPI wrote: ↑
Tue Apr 03, 2018 9:43 pmHey everyone,
Was curious about what functions that Power Management Chip does on the Raspberry Pi 3B+, I know it says it allows for better Signal transmission for power, but what else does it help Manage. If thats all it actually does, how does it do it compared to just using the fuses/resistors that was used previously?
Does the OS/Kernel have access to the PMC or does it do its own thing?
Thanks!
Here is the data sheet of the new power chip for your enjoyment: https://www.exar.com/ds/mxl7704.pdf
The older RPi’s B+, 2B & 3B had more than just fuses and resistors in the power circuitry.
Older RPi used this power chip: https://www.diodes.com/assets/Datasheets/PAM2306.pdf
The 3B and 3B+ have the same ‘polyfuse’ rated at 2.6A (hold current).
The 3B and 3B+ have the same over-voltage device – TVS diode.
The 3B+ does not seem to have the ideal diode circuit that older models have.
One thing to note is that the 3V3 current output on the 3B+ is now 1.5A. Older RPi’s were 1.0A per datasheets.
Probably most of the interaction with firmware is for configuring the chip at boot time.
The new chip does have two 8 bit ADC inputs and a temperature sensor. The ADC inputs are grounded out per schematic so not usable. Possibly the temp sensor could be accessed if firmware allows it?
Reference schematics
3B+: https://www.raspberrypi.org/documentati … ematic.pdf
3B: https://www.raspberrypi.org/documentati … matics.pdf
了解究竟哩☆☆