#Linux #GRUB Practical RecoveryFault Phenomenon and Root Cause Analysis After a system upgrade or unexpected power outage, the following prompt appears on boot: error: symbol 'grub_is_lockdown' not found. Entering rescue mode… grub rescue> This issue is common in Debian/Ubuntu system upgrade scenarios and is essentially a compatibility problem with the GRUB package or file corruption. … Read more
Traditional synchronous digital communication buses rely on two fundamental principles related to signal modulation and maximum likelihood sampling. In short, digital information transmission begins with representing information using data bits, which are then encoded into physical quantities such as voltage potentials or electronic currents. These physical quantities are transmitted through physical media such as metal … Read more
modetest -M rockchip ❝ When connecting an EDP interface display to the motherboard, if the error “LT CR Failure” (Link Training & Clock Recovery failure) occurs, the following are possible causes and solutions: 1. Core Reasons for Link Training Failure Poor Signal Integrity The EDP signals (differential pairs) from the motherboard to the display may … Read more