Decode vcgencmd

pi_decode_throttled.sh

#!/bin/bash

# Script: decode_throttled.sh
# Description: Decodes the output of 'vcgencmd get_throttled' on a Raspberry Pi
# Usage: ./decode_throttled.sh

# Run vcgencmd and capture the output
THROTTLED_HEX=$(vcgencmd get_throttled | cut -d'=' -f2)

# Remove '0x' prefix if present
THROTTLED_VAL=$((THROTTLED_HEX))

echo "========================================="
echo "Raspberry Pi Throttling Status Decoder"
echo "========================================="
echo "Raw value: $THROTTLED_HEX (decimal: $THROTTLED_VAL)"
echo ""

# Check if the value is zero (no issues)
if [ $THROTTLED_VAL -eq 0 ]; then
    echo "✅ Status: No throttling issues detected"
    echo "   Your Pi is running normally."
    exit 0
fi

echo "⚠️  Issues detected:"
echo ""

# Function to check a bit and print its meaning
check_bit() {
    local bit=$1
    local hex=$2
    local current_msg=$3
    local occurred_msg=$4
    
    if [ $(($THROTTLED_VAL & $hex)) -ne 0 ]; then
        # Check if it's a "current" bit (0-3) or "occurred" bit (16-19)
        if [ $bit -le 3 ]; then
            echo "   🔴 $current_msg (ACTIVE NOW)"
        else
            echo "   🟡 $occurred_msg (HAS OCCURRED SINCE BOOT)"
        fi
    fi
}

# Check each bit according to the table
check_bit 0 0x1 "Undervoltage detected" "Undervoltage has occurred"
check_bit 1 0x2 "Arm frequency capped" "Arm frequency capping has occurred"
check_bit 2 0x4 "Currently throttled" "Throttling has occurred"
check_bit 3 0x8 "Soft temperature limit active" "Soft temperature limit has occurred"

echo ""
echo "========================================="
echo "Recommendations:"
echo "========================================="

# Provide specific recommendations based on issues found
if [ $(($THROTTLED_VAL & 0x1)) -ne 0 ] || [ $(($THROTTLED_VAL & 0x10000)) -ne 0 ]; then
    echo "🔌 Power Issue:"
    echo "   - Use official Raspberry Pi 27W (5V/5A) USB-C power supply"
    echo "   - Check your USB-C cable (use short, thick gauge cable)"
    echo "   - If using Penta HAT, use dedicated 12V power supply"
    echo ""
fi

if [ $(($THROTTLED_VAL & 0x4)) -ne 0 ] || [ $(($THROTTLED_VAL & 0x40000)) -ne 0 ]; then
    echo "🌡️  Thermal Issue:"
    echo "   - Install official Raspberry Pi 5 Active Cooler"
    echo "   - Ensure adequate case ventilation"
    echo "   - Check for dust or blocked airflow"
    echo ""
fi

if [ $(($THROTTLED_VAL & 0x8)) -ne 0 ] || [ $(($THROTTLED_VAL & 0x80000)) -ne 0 ]; then
    echo "🔥 Temperature Warning:"
    echo "   - CPU temperature exceeded 80°C (soft limit)"
    echo "   - Improve cooling immediately"
    echo "   - Reduce CPU load or add active cooling"
    echo ""
fi

echo "For real-time monitoring, run: watch -n 1 'vcgencmd get_throttled && vcgencmd measure_temp'"