圖片來源:MxL7704 PMIC Powers the Raspberry Pi 4 樹莓派目前使用中的供電系統是在 3B+ 開始改用的。供電系統的好壞對樹莓派來說是非常重要,一個運作良好的供電系統可以確保整塊板子的各功能運作正常,一旦供電出問題時,可能對板子所有功能造成各種問題,例如 USB、WiFi 功能失效或不正常,最嚴重的慘況就是讓整塊板子完全停擺變成一塊磚頭。 《供電系統之演進》 樹莓派供電系統的演進可以分成三個階段: 《第一階段是 Pi2 以前的供電》 重點提示:這代整體的供電源頭是來自於 Micro USB 5V,再轉換成 3.3V、2.5V、1.8V等部份供給系統上元件使用。 圖片來源:Introducing the Raspberry Pi Model B+ 接著來看看電路圖了解電源是怎開始的。電源從左側MICRO USB TYPE B這接頭端開始,經過 F3 保險絲再來到 D17 TVS(Transient voltage suppressor)及後端的濾波電容。 這樣的電路設計有什麼優點: 電路設計簡單,價錢便宜。 … Continue reading →
很多人拿到 Pi 3B+ 之後會迫不及待的把原本在 Pi 3B 上所使用的 SD 卡拿到 Pi 3B+ 使用,但是會發現無法開機。這是因為 Pi 3B+ 使用新的晶片(BCM2837B0),因此如果沒有安裝 2018-03-13 以後所發布的核心(kernel)或是韌體(firmware)是無法直接使用的。
2018-03-13:
* Raspberry Pi 3 B+ support
* WiFi is disabled until wireless regulatory domain is set (Pi 3 B+ only)
- The domain can be done through 'Raspberry Pi Configuration' (rc_gui),
'raspi-config' or by setting 'country=' to an appropriate ISO 3166
alpha2 country code in /etc/wpa_supplicant/wpa_supplicant.conf.
$ sudo rfkill unblock wifi
$ sudo rfkill list
0: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
1: hci0: Bluetooth
Soft blocked: no
Hard blocked: no
Pi 3B+ 這次新增了 MaxLinear MxL7704 電源管理 IC,可有更好的溫度管理策略。例如在 70°C 以下可以使用 1.4GHz 全速運轉;但超過了 70°C 就會降到 1.2GHz 的速度。可用 Sysbench 看溫度/頻率的曲線圖。
圖片來源:RASPBERRY PI 3 MODEL B+ ON SALE NOW AT $35
2018-03-13:
* Raspberry Pi 3 B+ support
* WiFi is disabled until wireless regulatory domain is set (Pi 3 B+ only)
- The domain can be done through 'Raspberry Pi Configuration' (rc_gui),
'raspi-config' or by setting 'country=' to an appropriate ISO 3166
alpha2 country code in /etc/wpa_supplicant/wpa_supplicant.conf.
* Default wireless regulatory domain is now unset
* Added support to desktop for different screen sizes and resolutions,
including multiple preset options in Appearance Settings and pixel doubling
option in Raspberry Pi Configuration
* Version 2.1.16 of Thonny included
* Version 29.0.0.113 of Adobe PepperFlash player included
* Version 1.2.post1 of Pygame Zero included
* Bluetooth plugin now supports connection to Bluetooth LE HID devices
* Network plugin now indicates 5G-compatible APs
* Latest changes to Bluez ALSA service merged
- service now started on CLI boot as well as GUI boot
* Latest changes to dhcpcd networking plugin merged
* Improved support for running on pi-top devices
* Small design changes to PiX theme and icons
* Bug fix - hide spurious window resize handles
* Bug fix - Scratch 2 remote GPIO state block now works correctly
* Updated WiFi Firmware
- brcmfmac43455-sdio 7.45.154
- brcmfmac43430-sdio 7.45.98.38
* New packages:
- policykit-1
- obconf
- python-buttonshim python3-buttonshim
- python-unicornhathd python3-unicornhathd
- python-pantilthat python3-pantilthat
* Linux kernel 4.9.80+
* Raspberry Pi firmware 3347884c7df574bbabeff6dca63caf686e629699