《陶淵明‧桃花源詩》
嬴氏亂天紀,賢者避其世。
黃綺之商山,伊人亦云逝。
往跡浸復湮,來逕遂蕪廢。
相命肆農耕,日入從所憩。
桑竹垂餘蔭,菽稷隨時藝。
春蠶收長絲,秋熟靡王稅。
荒路曖交通,雞犬亙鳴吠。
俎豆猶古法,衣裳無新製。
童孺縱行歌,斑白歡游詣。
草榮識節和,木衰知風厲。
雖無紀歷志,四時自成歲。
怡然有餘樂,於何勞智慧。
奇蹤隱五百,一朝敞神界。
淳薄既異源,旋復還幽蔽。
借問游方士,焉測塵囂外?
願言躡輕風,高舉尋吾契。
傳聞說『未公開的特色』 Undocumented feature ︰
“It’s not a bug; it’s an undocumented feature!”
一詞來自早年 Microsoft 對於 Windows Bugs 的辯解。由於作者不知其詳,所以無法評論 WiKi 上的說法。僅就自身經驗上講︰ Intel 808x CPU 有未公開的指令, Microsoft DOS 有後門, Nintendo NES 遊戲有隱藏關卡,…… 卻彷彿是事實,或許說總有原因的吧!
自然是事出有因,當作者玩『 Compute Module 』時,就產生了『疑惑』,因曾『谷歌』天下說法,停止於『論壇討論』,本早已忘卻,近日為『 SD 卡讀寫機』壞了,一時情急方又記起此事,『驗證』之下果然 OK,在此特饗讀者。秘方︰A ⊕ B = ☆
得將之接於 USB Port 開機呦!!
# 開機時 dmesg [ 325.613553] usb 1-1.3: new full-speed USB device number 8 using dwc_otg [ 325.743695] usb 1-1.3: New USB device found, idVendor=0a5c, idProduct=2763 [ 325.743732] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 325.743747] usb 1-1.3: Product: BCM2708 Boot [ 325.743761] usb 1-1.3: Manufacturer: Broadcom # 使用祕笈程式 pi@raspberrypi ~ $ sudo rpiboot Waiting for BCM2835 ... Found serial = 0: writing file /usr/share/rpiboot/usbbootcode.bin Waiting for BCM2835 ... Found serial = 1: writing file /usr/share/rpiboot/msd.elf # 變成 SD 卡讀寫機 [ 411.387073] usb 1-1.3: USB disconnect, device number 8 [ 411.625027] usb 1-1.3: new high-speed USB device number 9 using dwc_otg [ 411.726194] usb 1-1.3: New USB device found, idVendor=0a5c, idProduct=2763 [ 411.726233] usb 1-1.3: New USB device strings: Mfr=1, Product=2, SerialNumber=1 [ 411.726252] usb 1-1.3: Product: Raspberry Pi [ 411.726267] usb 1-1.3: Manufacturer: Broadcom [ 411.726282] usb 1-1.3: SerialNumber: Broadcom [ 411.899098] usb 1-1.3: USB disconnect, device number 9 [ 412.904956] usb 1-1.3: new high-speed USB device number 10 using dwc_otg [ 413.006152] usb 1-1.3: New USB device found, idVendor=0a5c, idProduct=0001 [ 413.006192] usb 1-1.3: New USB device strings: Mfr=2, Product=1, SerialNumber=3 [ 413.006208] usb 1-1.3: Product: Compute Module [ 413.006223] usb 1-1.3: Manufacturer: Raspberry Pi [ 413.006235] usb 1-1.3: SerialNumber: 0001 [ 413.013771] usb-storage 1-1.3:1.0: USB Mass Storage device detected [ 413.020648] scsi0 : usb-storage 1-1.3:1.0 [ 414.016202] scsi 0:0:0:0: Direct-Access Raspberr y PiMass storage PQ: 0 ANSI: 2 [ 414.019761] sd 0:0:0:0: [sda] 15523840 512-byte logical blocks: (7.94 GB/7.40 GiB) [ 414.022586] sd 0:0:0:0: [sda] Write Protect is off [ 414.022629] sd 0:0:0:0: [sda] Mode Sense: 0f 00 00 00 [ 414.023232] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 414.030110] sda: sda1 [ 414.033888] sd 0:0:0:0: [sda] Attached SCSI removable disk [ 414.092978] sd 0:0:0:0: Attached scsi generic sg0 type 0 [ 414.934585] FAT-fs (sda1): Volume was not properly unmounted. Some data may be corrupt. Please run fsck. #編譯安裝 git clone --depth=1 https://github.com/raspberrypi/tools cd tools/usbboot/ make sudo make install
有圖為證︰
── 發現之快樂是單純的樂趣,何不樂在其中?? ──