vcgencmd
vcgencmd is a command-line tool for the Raspberry Pi that allows you to query the GPU firmware for various system and hardware information.
Installation
# Alpine Linux
apk add raspberrypi-utils-vcgencmd
Common Commands
System Information & Health
vcgencmd version # Show firmware version
vcgencmd measure_temp # Show GPU temperature
vcgencmd get_throttled # Check for under-voltage or overheating issues (see breakdown below)
vcgencmd measure_clock arm # Show ARM (CPU) clock frequency in Hz
vcgencmd measure_volts core # Show core voltage
Memory & Display
vcgencmd get_mem arm # Show memory allocated to ARM (CPU) in MB
vcgencmd get_mem gpu # Show memory allocated to GPU in MB
vcgencmd display_power 1 # Turn display power ON
vcgencmd display_power 0 # Turn display power OFF
Codecs & Hardware Acceleration
vcgencmd codec_enabled H264 # Check if H264 hardware codec is enabled
vcgencmd codec_enabled MJPEG # Check if MJPEG hardware codec is enabled
get_throttled Bitmask Breakdown
The value returned by vcgencmd get_throttled is a bitmask where each bit represents a specific state.
| Bit | Hex Value | Description |
|---|---|---|
| 0 | 0x1 | Under-voltage detected (Lightning bolt icon). |
| 1 | 0x2 | ARM frequency capped (Frequency limited). |
| 2 | `0x4** | Currently throttled. |
| 3 | 0x8 | Soft temperature limit active. |
| 16 | 0x10000 | Under-voltage has occurred since last reboot. |
| 17 | 0x20000 | ARM frequency capped has occurred since last reboot. |
| 18 | 0x40000 | Throttling has occurred since last reboot. |
| 19 | 0x80000 | Soft temperature limit has occurred since last reboot. |
Raw Output Examples
vcgencmd measure_volts Options
volt=0.8563V (core)
volt=1.1000V (sdram_c)
volt=1.1000V (sdram_i)
volt=1.1000V (sdram_p)
vcgencmd get_config int (Abbreviated)
arm_64bit=1
arm_freq=1500
core_freq=500
total_mem=1024