Bosse_B
Posts: 836
Joined: Thu Jan 30, 2014 9:53 am

Complete description of vcgencmd anywhere?

Mon Jul 15, 2019 3:02 pm

I just stumbled across the very useful vcgencmd program.
I wanted to read the CPU temperature and this is available like so:

Code: Select all

 $ vcgencmd measure_temp
temp=60.0'C
And the following command lists all available functions:

Code: Select all

$ vcgencmd commands
commands="vcos, ap_output_control, ap_output_post_processing, vchi_test_init, vchi_test_exit, vctest_memmap, vctest_start, vctest_stop, vctest_set, vctest_get, pm_set_policy, pm_get_status, pm_show_stats, pm_start_logging, pm_stop_logging, version, commands, set_vll_dir, set_backlight, set_logging, get_lcd_info, arbiter, cache_flush, otp_dump, test_result, codec_enabled, get_camera, get_mem, measure_clock, measure_volts, enable_clock, scaling_kernel, scaling_sharpness, get_hvs_asserts, get_throttled, measure_temp, get_config, hdmi_ntsc_freqs, hdmi_adjust_clock, hdmi_status_show, hvs_update_fields, pwm_speedup, force_audio, hdmi_stream_channels, hdmi_channel_map, display_power, read_ring_osc, memtest, dispmanx_list, get_rsts, schmoo, render_bar, disk_notify, inuse_notify, sus_suspend, sus_status, sus_is_enabled, sus_stop_test_thread, egl_platform_switch, mem_validate, mem_oom, mem_reloc_stats, hdmi_cvt, hdmi_timings, readmr, bootloader_version, file"
However I have failed to get a description of what is expected as arguments for the commands that need arguments (there are many)...
Is there a *complete* list of function arguments for vcgencmd?
(I googled and found this elinux page but that is incomplete, only listing a few cases.)
Bo Berglund
Sweden

trejan
Posts: 861
Joined: Tue Jul 02, 2019 2:28 pm

Re: Complete description of vcgencmd anywhere?

Mon Jul 15, 2019 3:50 pm

Bosse_B wrote: Is there a *complete* list of function arguments for vcgencmd?
No. Closest to official documentation is probably https://github.com/raspberrypi/document ... cgencmd.md but that isn't complete. A lot of the commands are for internal testing/development and have no public documentation. Everything else you'll need to dig around in the forum or do your own testing.

Bosse_B
Posts: 836
Joined: Thu Jan 30, 2014 9:53 am

Re: Complete description of vcgencmd anywhere?

Mon Jul 15, 2019 3:52 pm

Is the source for vcgencmd available?
Bo Berglund
Sweden

trejan
Posts: 861
Joined: Tue Jul 02, 2019 2:28 pm

Re: Complete description of vcgencmd anywhere?

Mon Jul 15, 2019 3:56 pm

Bosse_B wrote:
Mon Jul 15, 2019 3:52 pm
Is the source for vcgencmd available?
Yes but it doesn't show you anything useful since the commands are processed in the VideoCore firmware. vcgencmd will send anything you tell it.

deepo
Posts: 250
Joined: Sun Dec 30, 2018 8:36 pm

Re: Complete description of vcgencmd anywhere?

Wed Jul 17, 2019 7:22 am

trejan wrote:
Mon Jul 15, 2019 3:56 pm
Bosse_B wrote:
Mon Jul 15, 2019 3:52 pm
Is the source for vcgencmd available?
Yes but it doesn't show you anything useful since the commands are processed in the VideoCore firmware. vcgencmd will send anything you tell it.
Aaargh!

vcdgencmd send-more-money does not seem to work :)

/Mogens

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 24129
Joined: Sat Jul 30, 2011 7:41 pm

Re: Complete description of vcgencmd anywhere?

Wed Jul 17, 2019 9:20 am

What do you want to know?
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
“I think it’s wrong that only one company makes the game Monopoly.” – Steven Wright

Bosse_B
Posts: 836
Joined: Thu Jan 30, 2014 9:53 am

Re: Complete description of vcgencmd anywhere?

Wed Jul 17, 2019 12:01 pm

jamesh wrote:
Wed Jul 17, 2019 9:20 am
What do you want to know?
I would like to check all of the available commands but most require an unknown argument...
Bo Berglund
Sweden

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 24129
Joined: Sat Jul 30, 2011 7:41 pm

Re: Complete description of vcgencmd anywhere?

Fri Jul 19, 2019 10:25 am

Bosse_B wrote:
Wed Jul 17, 2019 12:01 pm
jamesh wrote:
Wed Jul 17, 2019 9:20 am
What do you want to know?
I would like to check all of the available commands but most require an unknown argument...
Most people have no need of using the majority of vcgencmd's. They are used internally for testing and debugging. The UI for vcgencmd is a bit pants. Could do with much better help, but since it's a debugging tool, it's unlikely to get much love.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
“I think it’s wrong that only one company makes the game Monopoly.” – Steven Wright

Bosse_B
Posts: 836
Joined: Thu Jan 30, 2014 9:53 am

Re: Complete description of vcgencmd anywhere?

Fri Jul 19, 2019 2:04 pm

OK, got it.
I only found it when googling for a way to check CPU temperature now that I have an RPi4 to experiment with....
Bo Berglund
Sweden

andrum99
Posts: 918
Joined: Fri Jul 20, 2012 2:41 pm

Re: Complete description of vcgencmd anywhere?

Fri Jul 19, 2019 4:46 pm

Here's some documentation that James created that has not yet made its way into the official documentation:

https://github.com/raspberrypi/document ... cgencmd.md

It's not complete, but it does document the options that are likely to be most useful to users.

ejolson
Posts: 3799
Joined: Tue Mar 18, 2014 11:47 am

Re: Complete description of vcgencmd anywhere?

Fri Jul 19, 2019 6:19 pm

andrum99 wrote:
Fri Jul 19, 2019 4:46 pm
Here's some documentation that James created that has not yet made its way into the official documentation:

https://github.com/raspberrypi/document ... cgencmd.md

It's not complete, but it does document the options that are likely to be most useful to users.
That's good documentation. Why, do you think, is it not available as a man page?

A reasonably complete and consistent documentation greatly helped people learn about Unix and programming in the beginning. Continuing that tradition seems in line with the Raspberry Pi Foundation's goal of computer literacy.

Return to “General discussion”