how to fix stuck permanent function (Fn) key

BIOS / Firmware updates: but why?

if everything works, vendors often say “leave it like that”

because updates can have unforseen sideeffects and not all computers are “exactly” the same X-D (a bit here and a bit there might be different)

BUT: BIOS Firmware as any other software that can contain bugs & security problems

concerning the t440 Lenovos, a security problem was discovered and fixed, so it is recommended to upgrade.

Lenovo t440 Debian 10 and very stylish Cimmanon Desktop (MATE is more minimalism)

Lenovo t440 Debian 10 and very stylish Cinnamon Desktop (MATE is more minimalism)

there were stability (kernel) issues with this laptop under Debian 9 + latest updates, dist-upgrade to Debian 10 seams to have fixed those (still testing).

GNU Linux (Debian 10 was intensively tested) is very well supported on those devices

  • lenovo offers superb performance per buck ratio (when a SSD is present)
  • some even come with keyboard backlighting (!!! highly recommended X-D it just looks great and also is better to find the keys in environments with low light)

two different power supplies: 90W and 45W

it is a bit strange, not all t440 are the same, some come with 45W power supply while others come with 90W power supply.

if a 45W power supply is connected to a 90W-t440 – it will refuse to charge the battery – and the power on LED button is blinking. just 4 info

should be fine to use 90W power supply on 45W t440, but not vice versa.

the software:

this is an CD.iso image!

unfortunately (tested) can not dd 1:1 copy it on a USB stick (tested 3x different sticks, does not work, some images.iso are strict CD.iso images and can not be used with USB sticks)

so either follow this very lengthy “how to make bios update stick under windows”

or download the cd.iso

(sha256sum: c0fb3b3cf64bf8b7ff0f5d05461d0fb4184e3eb31ac9d8494ae727b0410fe8e3)

and get some gear 🙂

the hardware:

USB to SATA adapter

this JMicron USB to SATA/IDE is VERY VERY OLD X-D (but it still works)

probably better (BUT UNTESTED!) to get a USB to SATA/IDE adapter from CSL.

the DVD drive

PLEXTOR does very high quality DVD-R drives

this PX-820SA one is also a bit old but works 🙂

it should also just work fine with a newer model

also the CD-R used should be of high quality such as Verbatim

# dmesg of USB to SATA Adapter
# there might be better USB to ATA/SATA bridges by now than JMicron might 
[11849.360668] usb 2-7: new high-speed USB device number 19 using xhci_hcd
[11849.510319] usb 2-7: New USB device found, idVendor=152d, idProduct=2338, bcdDevice= 1.00
[11849.510333] usb 2-7: New USB device strings: Mfr=1, Product=2, SerialNumber=5
[11849.510340] usb 2-7: Product: USB to ATA/ATAPI Bridge
[11849.510345] usb 2-7: Manufacturer: JMicron
[11849.510351] usb 2-7: SerialNumber: 000000000000
[11849.512343] usb-storage 2-7:1.0: USB Mass Storage device detected
[11849.513148] scsi host6: usb-storage 2-7:1.0
[11850.522217] scsi 6:0:0:0: CD-ROM            PLEXTOR  DVD-R   PX-820SA  1.01 PQ: 0 ANSI: 0
[11850.524259] sr 6:0:0:0: Power-on or device reset occurred
[11850.527256] sr 6:0:0:0: [sr0] scsi3-mmc drive: 48x/48x writer dvd-ram cd/rw xa/form2 cdda tray
[11850.527519] sr 6:0:0:0: Attached scsi CD-ROM sr0
[11850.527645] sr 6:0:0:0: Attached scsi generic sg2 type 5
[11852.129203] sr 6:0:0:0: [sr0] tag#0 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[11852.129223] sr 6:0:0:0: [sr0] tag#0 Sense Key : Illegal Request [current] 
[11852.129235] sr 6:0:0:0: [sr0] tag#0 Add. Sense: Illegal mode for this track
[11852.129244] sr 6:0:0:0: [sr0] tag#0 CDB: Read(10) 28 00 00 00 40 b6 00 00 02 00
[11852.129251] print_req_error: I/O error, dev sr0, sector 66264
[11852.129302] attempt to access beyond end of device
[11852.129313] sr0: rw=0, want=66272, limit=66264
[11852.129324] Buffer I/O error on dev sr0, logical block 8283, async page read
[11855.883506] ISO 9660 Extensions: Microsoft Joliet Level 3
[11855.926596] ISOFS: changing to secondary root
[11856.057992] Buffer I/O error on dev dm-4, logical block 0, async page read
[11856.058005] Buffer I/O error on dev dm-4, logical block 0, async page read
[11856.058068] Buffer I/O error on dev dm-4, logical block 0, async page read
[11856.058075] Buffer I/O error on dev dm-4, logical block 0, async page read

of course

there are also the all-in-one-usb-dvd-r-solutions

burn the iso to CD-R

brasero does this job nicely, chose 16x speed is enough, what brasero also will do: double check if data was written correctly 🙂 (VERY GOOD JOB! 🙂

reset BIOS to default settings

during startup hit [ENTER] to interrupt startup

then hit F1 to enter bios

hit F9 to restore default settings

hit F10 to save restore of default settings

now wait until “Configuration changed – restarting system” is shown (which confirms restore of defaults)

ready to flash

  • disconnect power of USB-SATA/IDE adapter
  • connect power to USB-SATA/IDE adapter
  • during boot hit F12
  • the PLEXTOR “should” be visible in the list of devices
    • sometimes it takes a while, try different USB ports power on/power off


let it do it’s work… it will now display

“upgrading internal adapter”

and then it is finished.



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