measure_volts_rpi.sh

#!/usr/bin/env bash
# @title: Measure Voltage RPi
# @description: Display Raspberry Pi voltage and checks if it is undervolted.
# Tested on Raspberry Pi OS (RPi 4)

for id in core sdram_c sdram_i sdram_p; do
    echo -e "$id:\t$(vcgencmd measure_volts $id)"
done

# Flag Bits
UNDERVOLTED=0x1
CAPPED=0x2
THROTTLED=0x4
HAS_UNDERVOLTED=0x10000
HAS_CAPPED=0x20000
HAS_THROTTLED=0x40000

# Text Colors
GREEN=$(tput setaf 2)
RED=$(tput setaf 1)
NC=$(tput sgr0)

# Output Strings
GOOD="${GREEN}NO${NC}"
BAD="${RED}YES${NC}"

# Get Status, extract hex
STATUS=$(vcgencmd get_throttled)
STATUS=${STATUS#*=}

echo -n "Status: "
((STATUS != 0)) && echo "${RED}${STATUS}${NC}" || echo "${GREEN}${STATUS}${NC}"

echo "Undervolted:"
echo -n "   Now: "
(((STATUS & UNDERVOLTED) != 0)) && echo "${BAD}" || echo "${GOOD}"
echo -n "   Run: "
(((STATUS & HAS_UNDERVOLTED) != 0)) && echo "${BAD}" || echo "${GOOD}"

echo "Throttled:"
echo -n "   Now: "
(((STATUS & THROTTLED) != 0)) && echo "${BAD}" || echo "${GOOD}"
echo -n "   Run: "
(((STATUS & HAS_THROTTLED) != 0)) && echo "${BAD}" || echo "${GOOD}"

echo "Frequency Capped:"
echo -n "   Now: "
(((STATUS & CAPPED) != 0)) && echo "${BAD}" || echo "${GOOD}"
echo -n "   Run: "
(((STATUS & HAS_CAPPED) != 0)) && echo "${BAD}" || echo "${GOOD}"