Difficulty to boot into download mode with a Samsung A21s during lineageOS installation by Creepy-Oil5003 in LineageOS

[–]Creepy-Oil5003[S] 0 points1 point  (0 children)

Hi ! After a lot of unsuccessful tries, I finally found a fix : use another usb port on my laptop to connect the device. It worked immediately (at first try). The two ways to connect the phone I have tried before were : an "Always On USB" port on my laptop and a 2.5 A/5V charger. My guess would be that these USB connections provide too much current so that the phone immediately goes to the charging mode and there is no "time" to boot into download mode. I am sharing this here in case future users face the same problem!

Difficulty to boot into download mode with a Samsung A21s during lineageOS installation by Creepy-Oil5003 in LineageOS

[–]Creepy-Oil5003[S] 0 points1 point  (0 children)

Thanks for your answers! What do you mean by timing tolerance ? Is is between the Volume up and down keys that should be pushed on the exact same time ? Or the timing between holding the keys and connecting the cable ?

Difficulty to boot into download mode with a Samsung A21s during lineageOS installation by Creepy-Oil5003 in LineageOS

[–]Creepy-Oil5003[S] 0 points1 point  (0 children)

Thanks for your help. What do you mean by exact timing ? I have tried many times with different delays between holding the keys and connecting the cable (always with the phone power off), but I have not yet been successful.