Command detect
Syntax: detect <options>
Scans the system for displays supporting the Monitor Control Command Set (MCCS), most commonly using DDC/CI but alternatively using USB for communication. This command reports the results of the display search, which also is performed in the background as part of most ddcutil commands.
Option --async
If there are 3 or more monitors and option --async is specified, initial monitor DDC checks are performed in separate threads. marginally improving startup time.
Option: --enable-usb/--disable-usb
This pair of options controls whether ddcutil searches for displays that use USB for communication. The default is --disable-usb.
Although the overhead of searching for USB displays has a negligable effect on ddcutil performance, the benign error messages it can produce regarding permissions
have proven distracting.
USB display support is rarely required, as most monitors use DDC/CI, not USB, for MCCS communication.
The output varies by verbosity.
Normal output:
$ ddcutil detect
Display 1<
I2C bus: /dev/i2c-7
EDID synopsis:
Mfg id: ACR
Model: Acer X243W
Serial number: LAG040064310
Manufacture year: 2007
EDID version: 1.3
VCP version: 2.1
Display 2
I2C bus: /dev/i2c-8
EDID synopsis:
Mfg id: DEL
Model: DELL P2411H
Serial number: F8NDP11G119U
Manufacture year: 2011
EDID version: 1.3
VCP version: 2.1
Display 3
I2C bus: /dev/i2c-10
EDID synopsis:
Mfg id: HWP
Model: HP Z22i
Serial number: CNC51301ZP
Manufacture year: 2015
EDID version: 1.3
VCP version: 2.2
Display 4
I2C bus: /dev/i2c-14
EDID synopsis:
Mfg id: DEL
Model: DELL U3011
Serial number: PH5NY2CIANXL
Manufacture year: 2012
EDID version: 1.4
VCP version: 2.1
Option: --brief, --terse
Presents a summary report of each detected display, in an easily machine readable form.
$ ddcutil detect --brief
Display 1
I2C bus: /dev/i2c-7
Monitor: ACR:Acer X243W:LAG040064310
Display 2
I2C bus: /dev/i2c-8
Monitor: DEL:DELL P2411H:F8NDP11G119U
Display 3
I2C bus: /dev/i2c-10
Monitor: HWP:HP Z22i:CNC51301ZP
Display 4
I2C bus: /dev/i2c-14
Monitor: DEL:DELL U3011:PH5NY2CIANXL
Option: ***--verbose ***
Show additional information, including the EDID.
$ ddcutil detect --verbose
Display 1
I2C bus: /dev/i2c-7
I2C address 0x50 (EDID) responsive: true
Is eDP device: false
I2C address 0x37 (DDC) responsive: true
/sys/bus/i2c/devices/i2c-7/name: AMDGPU i2c bit bus 0x92
EDID synopsis:
Mfg id: ACR
Model: Acer X243W
Serial number: LAG040064310
Manufacture year: 2007
EDID version: 1.3
Product code: 0
Binary sn: 1952453327 (0x746012cf)
Extra descriptor:
Video input definition: 0x80 - Digital Input
Supported features:
DPMS active-off
Digital display type: RGB 4:4:4
Standard sRGB color space: False
White x,y: 0.313, 0.329
Red x,y: 0.640, 0.330
Green x,y: 0.300, 0.608
Blue x,y: 0.150, 0.060
Extension blocks: 0
EDID source:
EDID hex dump:
+0 +4 +8 +c 0 4 8 c
+0000 00 ff ff ff ff ff ff 00 04 72 00 00 cf 12 60 74 .........r....`t
+0010 2e 11 01 03 80 34 20 78 2a ef 95 a3 54 4c 9b 26 .....4 x*...TL.&
+0020 0f 50 54 a5 4b 00 81 80 81 00 81 0f 95 00 95 0f .PT.K...........
+0030 a9 40 b3 00 01 01 28 3c 80 a0 70 b0 23 40 30 20 .@....(<..p.#@0
+0040 36 00 06 44 21 00 00 1a 00 00 00 fd 00 38 4c 1e 6..D!........8L.
+0050 52 11 00 0a 20 20 20 20 20 20 00 00 00 fc 00 41 R... .....A
+0060 63 65 72 20 58 32 34 33 57 0a 20 20 00 00 00 ff cer X243W. ....
+0070 00 4c 41 47 30 34 30 30 36 34 33 31 30 0a 00 68 .LAG040064310..h
VCP version: 2.1
Controller mfg: Mstar
Firmware version: 0.3
Monitor returns DDC Null Response for unsupported features: false
Display 2
I2C bus: /dev/i2c-8
I2C address 0x50 (EDID) responsive: true
Is eDP device: false
I2C address 0x37 (DDC) responsive: true
/sys/bus/i2c/devices/i2c-8/name: AMDGPU i2c bit bus 0x93
EDID synopsis:
Mfg id: DEL
Model: DELL P2411H
Serial number: F8NDP11G119U
Manufacture year: 2011
EDID version: 1.3
Product code: 41070
Binary sn: 825309525 (0x31313955)
Extra descriptor:
Video input definition: 0x80 - Digital Input
Supported features:
DPMS standby
DPMS suspend
DPMS active-off
Digital display type: RGB 4:4:4
Standard sRGB color space: False
White x,y: 0.313, 0.328
Red x,y: 0.631, 0.351
Green x,y: 0.334, 0.620
Blue x,y: 0.156, 0.051
Extension blocks: 0
EDID source:
EDID hex dump:
+0 +4 +8 +c 0 4 8 c
+0000 00 ff ff ff ff ff ff 00 10 ac 6e a0 55 39 31 31 ..........n.U911
+0010 04 15 01 03 80 35 1e 78 ea bb 04 a1 59 55 9e 28 .....5.x....YU.(
+0020 0d 50 54 a5 4b 00 71 4f 81 80 d1 c0 01 01 01 01 .PT.K.qO........
+0030 01 01 01 01 01 01 02 3a 80 18 71 38 2d 40 58 2c .......:..q8-@X,
+0040 45 00 13 2b 21 00 00 1e 00 00 00 ff 00 46 38 4e E..+!........F8N
+0050 44 50 31 31 47 31 31 39 55 0a 00 00 00 fc 00 44 DP11G119U......D
+0060 45 4c 4c 20 50 32 34 31 31 48 0a 20 00 00 00 fd ELL P2411H. ....
+0070 00 38 4c 1e 53 11 00 0a 20 20 20 20 20 20 00 63 .8L.S... .c
VCP version: 2.1
Controller mfg: Mstar
Firmware version: 1.1
Monitor returns DDC Null Response for unsupported features: false
Display 3
I2C bus: /dev/i2c-10
I2C address 0x50 (EDID) responsive: true
Is eDP device: false
I2C address 0x37 (DDC) responsive: true
/sys/bus/i2c/devices/i2c-10/name: AMDGPU i2c bit bus 0x95
EDID synopsis:
Mfg id: HWP
Model: HP Z22i
Serial number: CNC51301ZP
Manufacture year: 2015
EDID version: 1.3
Product code: 12428
Binary sn: 16843009 (0x01010101)
Extra descriptor:
Video input definition: 0x80 - Digital Input
Supported features:
DPMS active-off
Digital display type: RGB 4:4:4
Standard sRGB color space: False
White x,y: 0.313, 0.329
Red x,y: 0.647, 0.339
Green x,y: 0.307, 0.633
Blue x,y: 0.146, 0.056
Extension blocks: 0
EDID source:
EDID hex dump:
+0 +4 +8 +c 0 4 8 c
+0000 00 ff ff ff ff ff ff 00 22 f0 8c 30 01 01 01 01 ........"..0....
+0010 0d 19 01 03 80 30 1b 78 2e f8 55 a5 56 4e a2 25 .....0.x..U.VN.%
+0020 0e 50 54 a1 08 00 d1 c0 81 c0 81 80 95 00 a9 c0 .PT.............
+0030 b3 00 01 01 01 01 02 3a 80 18 71 38 2d 40 58 2c .......:..q8-@X,
+0040 45 00 dd 0c 11 00 00 1e 00 00 00 fd 00 32 4c 18 E............2L.
+0050 5e 11 00 0a 20 20 20 20 20 20 00 00 00 fc 00 48 ^... .....H
+0060 50 20 5a 32 32 69 0a 20 20 20 20 20 00 00 00 ff P Z22i. ....
+0070 00 43 4e 43 35 31 33 30 31 5a 50 0a 20 20 00 7c .CNC51301ZP. .|
VCP version: 2.2
Controller mfg: Mstar
Firmware version: 1.0
Monitor returns DDC Null Response for unsupported features: false
Display 4
I2C bus: /dev/i2c-14
I2C address 0x50 (EDID) responsive: true
Is eDP device: false
I2C address 0x37 (DDC) responsive: true
/sys/bus/i2c/devices/i2c-14/name: card0-DP-2
EDID synopsis:
Mfg id: DEL
Model: DELL U3011
Serial number: PH5NY2CIANXL
Manufacture year: 2012
EDID version: 1.4
Product code: 16485
Binary sn: 1095653452 (0x414e584c)
Extra descriptor:
Video input definition: 0xb5 - Digital Input (DisplayPort)
Supported features:
DPMS active-off
Digital display type: RGB 4:4:4 + YCrCb 4:2:2
Standard sRGB color space: True
White x,y: 0.313, 0.329
Red x,y: 0.678, 0.309
Green x,y: 0.210, 0.692
Blue x,y: 0.146, 0.055
Extension blocks: 1
EDID source:
EDID hex dump:
+0 +4 +8 +c 0 4 8 c
+0000 00 ff ff ff ff ff ff 00 10 ac 65 40 4c 58 4e 41 ..........e@LXNA
+0010 33 16 01 04 b5 40 28 78 3a 8d 85 ad 4f 35 b1 25 3....@(x:...O5.%
+0020 0e 50 54 a5 4b 00 71 4f 81 00 81 80 a9 40 d1 00 .PT.K.qO.....@..
+0030 d1 40 01 01 01 01 e2 68 00 a0 a0 40 2e 60 30 20 .@.....h...@.`0
+0040 36 00 81 91 21 00 00 1a 00 00 00 ff 00 50 48 35 6...!........PH5
+0050 4e 59 32 43 49 41 4e 58 4c 0a 00 00 00 fc 00 44 NY2CIANXL......D
+0060 45 4c 4c 20 55 33 30 31 31 0a 20 20 00 00 00 fd ELL U3011. ....
+0070 00 31 56 1d 71 1c 00 0a 20 20 20 20 20 20 01 56 .1V.q... .V
VCP version: 2.1
Controller mfg: Mstar
Firmware version: 1.5
Monitor returns DDC Null Response for unsupported features: false