Lenovo ThinkPad T420

type-model: 4236-P3G
cpu: Intel i5-2520M @ 2.5 GHz
memory: 4GB (max is 16 GB - 2 x 8 GB) 2 x SO-DIMM PC3-10600
display: 14 inch LCD, 1366x768
graphics: Intel HD Graphics
storage: 2.5 inch sata drive
optical drive: CDRW / DVDRW
network - wired: 1 Gbps Ethernet
network - wireless: Intel 802.11agn
camera
bluetooth
usb
UltraNav
fingerprint reader
secure chip (TPM?)

battery: 6c Li-Ion

UEFI (bios): 83ET82WW (1.52), 2018-06-04

serial number(s): PB477NC,

Links

Lenovo PSREF, PC Support: ThinkPad T420, coreboot: flashing firmware tutorial - T420 - Lenovo Sandy Bridge series - Board:lenovo/t420, Gentoo: Coreboot, Libreboot: - no T420 - SeaBIOS, ThinkWiki: T420, me_cleaner,

coreboot info

Waltibaba/coreboot_config_t420_2017_02, Waltibaba/flash t420 coreboot, coreboot-for-the-lenovo-t420-t420i-with-ivy-bridge-support, flash-lenovo-x230-coreboot, flashrom info: RaspberryPi, more info: gch1p/thinkpad-bios-software-flashing-guide, MX25L6406E,

3d-print models

Thinkpad T520 SSD Mount, T440s HDD caddy, HDD rails for my ThinkPad x200s,

OS tested: FreeBSD,

back to machines page.

History / work log

2021-07-20: I re-created this page on my self-hosted web server.

2020-09-05: flashrom - with a bluepill ans stm32-vserprog - not sure this is supposed to work

tingo@kg-elitebook:/zs/tingo/work/bitraf/2020/20200904_thinkpad_T420_coreboot/roms$ sudo flashrom -p serprog:dev=/dev/ttyACM0:4000000 --chip MX25L6406E/MX25L6408E
flashrom  on Linux 4.19.0-9-amd64 (x86_64)
flashrom is free software, get the source code at https://flashrom.org

Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
serprog: Programmer name is "stm32-vserprog"
No EEPROM/flash device found.
Note: flashrom can never write if the flash chip isn't found automatically.

switching MISO / MOSI does

tingo@kg-elitebook:/zs/tingo/work/bitraf/2020/20200904_thinkpad_T420_coreboot/roms$ sudo flashrom -p serprog:dev=/dev/ttyACM0:4000000
flashrom  on Linux 4.19.0-9-amd64 (x86_64)
flashrom is free software, get the source code at https://flashrom.org

Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
serprog: Programmer name is "stm32-vserprog"
serprog: requested mapping AT45CS1282 is incompatible: 0x1080000 bytes at 0x00000000fef80000.
No EEPROM/flash device found.
Note: flashrom can never write if the flash chip isn't found automatically.

not change anything.

2020-09-04: flashrom - trying to read the flash rom via flashrom on a Pi 3B+

tingo@flasher-pi:~/roms $ flashrom -p linux_spi:dev=/dev/spidev0.0,spispeed=128 --chip MX25L6406E/MX25L6408E
flashrom  on Linux 5.4.51-v7+ (armv7l)
flashrom is free software, get the source code at https://flashrom.org

Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns).
No EEPROM/flash device found.
Note: flashrom can never write if the flash chip isn't found automatically.

hmmm...

2020-01-13: tested the other T420 with a psu at Bitraf today. It has serial number PB477ZH, 4096MB RAM, uefi 1.52.

2020-01-10: memory upgrade - this will probably work (2 x 8).

2020-01-10: uefi - newest is 1.52

2020-01-10: I found a Lenovo 90W power adapter (partno: 92P1107), and plugged it into the laptop with serial number PB477NC

2020-01-10: I created this page.

2019-12-??: I got a couple of T420's for free. Both have 4 GB RAM. Both are missing the hard drive bays, one is missing the hard drive cover.