RPI vcgencmd usage

/opt/vc/bin/vcgencmd commands

Shows a list of possible (needs verification) commands.

Verified commands:

vcgencmd measure_clock

Shows clock frequency, clock can be one of arm, core, h264, isp, v3d, uart, pwm, emmc, pixel, vec, hdmi, dpi.

vcgencmd measure_volts 

Shows voltage, id can be one core, sdram_c, sdram_i, sdram_p, and defaults to core if not specified.

vcgencmd measure_temp

Shows core temperature of BCM2835 SoC.

vcgencmd codec_enabled

Shows if the specified codec is enabled, codec can be one of H264 MPG2 WVC1

vcgencmd version

Shows the firmware version

Parameters and function of other commands are not known. Current (version 337302) output of vcgencmd commands:

vcos, ap_output_control, ap_output_post_processing, pm_set_policy, pm_get_status, pm_show_stats, pm_start_logging, pm_stop_logging, version, commands, set_vll_dir, led_control, set_backlight, set_logging, get_lcd_info, set_bus_arbiter_mode, cache_flush, otp_dump, codec_enabled, measure_clock, measure_volts, measure_temp, hdmi_ntsc_freqs, render_bar, disk_notify, inuse_notify, sus_suspend, sus_status, sus_is_enabled, sus_stop_test_thread, egl_platform_switch, vctest_memmap, vctest_start, vctest_stop, vctest_set, vctest_get