Notes on Specific Monitors
+Information about specific monitors is now maintained on the +ddcutil repo wiki, which any github user can modify. This page is no longer maintained.
+The following list describes some monitors that have been tested or reported by users. It highlights the variability in DDC implementation among monitors.
+AOC Q2775
+VCP Version: 2.2
+Controller Manufacturer: Mstar
+Controller Model: mh=0xff, ml=0x16, sh=0x00
+Firmware version: 0.7
+Manufacture year: 2016
Feature x0B: Color temperature increment: 100 deg Kelvin
+Feature x0C: Color temperature request: 100
+Caclculated color temperature = 3000 + 100 * 100 = 3000+10000 = 13000 deg Kelvin (nonsensical)
Capabilities string has controller manufacturer name in model() field.
+Apple Cinema Display A1082
+Has both I2C and USB interfaces.
+VCP Version: 2.0
+Controller Manufacturer: unspecified
+Controller Model: unspecified
+Firmware version: unspecified
+Manufacture year: 2005
I2C interface has more VCP features than USB interface.
+USB interface does not report VCP version (feature DF).
+Able to read EDID over USB.
+Capabilities string does not begin and end with parentheses.
+Asus MG279
+The capabilities string is malformed.
+Asus PG329Q
+VCP version 2.2 +Controller Manufacturer: Novatek +Firmware version: 0.36 +Manufacture year: 2020
+The EDID contains neither an ASCII nor a binary serial number.
+Asus ROG PG279Q
+VCP version: 2.2
+Controller Manufacturer: manufacturer defined controller
+Controller Model:
+Firmware version: 5.57, 5.59
+Maufacture year: 2017, 2018
Does not support VCP codes x0B and X0C.
+Does not support feature x60 - Input Source
+Does not respond to getvcp of unsupported VCP codes by setting the unsupported feature flag in the GETVCP +response. Requests for unsupported features return garbage bytes, the requests fail by exceeding retries.
+The output of the capabilities command does appear to accurately report which features are supported.
+Asus VE247
+VCP version: 2.0
+Controller Manufacturer: RealTek
+Controller Model: mh=x00, ml=x24, sh=x82
+Firmware version: 2.0
+Maufacture year: 2010
Responds to unknown VCP codes using the DDC NULL message instead of setting the Unsupported VCP code bit in the GETVCP response.
+Sensible responses to VCP codes x0B and x0C.
+Asus VS248
+The value of feature x60 (Input Source) can be changed only from the currently active input.
+BenQ GW2480
+VCP Version: 2.1
+Controller Manufacturer: Mstar
+Controller Model: mh=0x00, ml=0x58, sh=0x00
+Firmware version: 3.10
+Manufacture year: 2018
Color temperature increment (x0b) = 50 degrees Kelvin
+Color temperature request (x0c) = 70
+Requested color temperature = (3000 deg Kelvin) + 70 * (50 degrees Kelvin) = 6500 degrees Kelvin
Brightness and possibly other color related features are disabled when +Dynamic Contrast Range (DCR) is enabled (using OSD).
+BenQ XL2411Z
+VCP version: 2.2
+Controller Manufacturer: Mstar
+Controller Model: mh=x00 mh=x00, ml-x85, sh=x56
+Firmware version: 2.1
+Manufacture year: 2013
Feature x0B: Color temperature increment: 50 deg Kelvin
+Feature x0C: Color temperature request: 0
+Caclculated color temperature = 3000 + (0*50) = 3000 deg Kelvin (nonsensical)
Responds to VCP feature x60 (Input Source) even though this is not documented in the capabilities string.
+ +Dell AW3418DW
+VCP Version: 2.2
+Controller Manufacturer: manufacturer designed (sl=0xff)
+Controller Model: mh=0x01 ml=0x08 sh=0x04
+Firmware version: 4.133
+Manufacture year: 2017
Feature x0B: Color temperature increment: unsupported
+Feature x0C: Color temperature request: unsupported
Reading unsupported feature 0x00 returns normally, with ml=ml=sh=sl=0. The unsupported feature bit is not set. +Reading any other unsupported feature value results in an IOCTL failure with Linux errno=EIO (5).
+ +Dell P2411
+VCP version: 2.1
+Controller Manufacturer: Mstar
+Controller Model: mh=x00, ml=x00, sh=x56
+Firmware version: 1.1
+Manufacture year: 2011
Lots of I2C errors. Heavily dependant on retries. The CAPABILITIES command sometimes fails, even with maximum retries. +More recently, works with nouveau driver, but fails with proprietary Nvidia driver.
+Reports VCP code 0B (color temperature increment) as 1 degree Kelvin, which makes the GETVCP response to VCP code 0C (color temperature +request) nonsensical.
+ +Dell P2715Q
+VCP version: 2.1
+Controller Manufacturer: Mstar (sl=x05)
+Controller Model: mh=x00, ml=x00,x sh=x56
+Firmware version: 2.1
+Manufacture year: 2015
Feature x0B, Color temperature increment: unsupported
+Feature x0C, Color temperature request: unsupported
very clean, no DDC retries needed
+ +Dell S3422DWG
+VCP version: 2.1 +Controller Manufacturer: RealTek (sl=0x09) +Controller Model: mh=0x00, ml=0x27, sh=0x17 +Firmware version: 65.3 +Manufacture year: 2021
+Github user Noctivans has posted extensive notes detailing what he discovered on how to +control Picture In Picture/Picture By Picture using undocumented features.
+ +Dell Ultrasharp 1905FP
+Does not support DDC.
+ +Dell Ultrasharp U2413
+VCP version: 2.1
+Controller Manufacturer: STMicroelectronics (sl=x0d)
+Controller Model: mh=x00, ml=x93, sh=x01
+Firmware version: 2.1
+Manufacture year: 2013
This monitor has a hardware LUT, however LUT loading not supported using standard VCP feature codes.
+Responds to VCP feature xc0 (Display Usage Time), but returns 0.
+Color temperature:
+ color temp increment (feature 0B): unsupported
+ color temp request (feature 0C): unsupported
Dell 2407wfp
+VCP version: 2.0
+Controller Manufacturer: Genesis
+Controller Model: mh=0xff, ml=0xff, sh=0x4a
+Firmware version: 29.1
Cannot set brightness less than 30. setvcp values in the range 0..50 are mapped to the range 30..50
+User eskampie created the following table.
+| Requested setvcp value | +Observed OSD value | +
|---|---|
| 0 | +30 | +
| 10 | +34 | +
| 20 | +38 | +
| 30 | +42 | +
| 40 | +46 | +
| 50 | +50 | +
| 60 | +60 | +
| 70 | +70 | +
| 80 | +80 | +
| 90 | +90 | +
| 100 | +100 | +
Dell U2518D
+VCP Version: 2,1
+Controller Manufacturer: MStar
+Controller Model: mh=0x00, ml=0x00, sh=0x56
+Firmware version: 2.1
+Manufacture year: 2018
Features 0B, 0C are unsupported.
+Attempting to set feature x12 (contrast) less than 25 results in a value of 25. +However, it is possible to set a lower contrast value in the OSD .
+Unlike the Dell 2404wfp feature x10 (brightness) can be set to any value between 0..100.
+Clean implementation, no I2c retries required.
+ +Dell U3011
+VCP version: 2.1
+Controller manufacturer: Mstar
+Controller Model: mh=x00, ml=x94, sh=x85
+Firmware version: 1.5
+Manufacture year: 2012
If a value is set using SETVCP, the new value takes effect and may appear in the on-screen display. However, GETVCP (or the verification option) sometimes still retieves the old value, not the new one. More specifically:
+| Feature Name | +Code | +Notes | +
|---|---|---|
| Contrast | +x12 | +values below x25 take effect but the old value is returned | +
| Video Gain: Red | +x16 | +Values below 100 take effect, but the GETVCP reports 100 | +
| Video Gain: Green | +x18 | +Ditto | +
| Video Gain: Blue | +x1a | +Ditto | +
| Display Mode | +xdc | ++ |
Reports VCP code x0B (color temperature increment) as 1 degree Kelvin, which makes the GETVCP response to +VCP code x0C (color temperature request) nonsensical.
+Color temperature:
+ color temp increment (feature 0B): 1 deg K
+ color temp request (feature 0C): 2
+ calculated color temp = 3000 + (x0c_val * x0b_val) = 3000 + (1 * 2) = 3002 degrees Kelvin
Dell Ultrasharp U3415W
+VCP version: 2.1
+Controller manufacturer: Realtek (sl=x09)
+Controller Model: mh=x00, ml=x11, sh=x11
+Firmware version: 65.1
+Manufacture year: 2015
Neither feature 0B (color temperature increment) or 0C (color temperature request) are listed +in the capabilities string. +However, querying feature 0B does work. Querying feature 0C fails.
+Color temperature:
+ color temp increment (feature 0B): 100 deg K
+ color temp request (feature 0C): query fails
Dell U3818DW
+VCP version: 2.1
+Controller Manufacturer: RealTek
+Controller Model: mh=0x00, ml=0x11, sh=0x11
+Firmware version: 65.1
+Manufacture year: 2017
Fails to set the Unsupported VCP Code bit in the getvcp response packet for unsupported features.
+ +Eizo Coloredge CG19
+VCP version: unreported
+Controller manufacturer and model: unreported (VCP feature code C8 unsupported)
+Firmware version: unreported (VCP feature code C9 unsupported)
Reports EDID at I2C bus address x50. Does not support DDC over I2C (bus address x37).
+Does implement MCCS over USB, and appears to conform to the USB Monitor Control Class Specification. +However, it appears that the more sophisticated monitor features such as LUT loading use manufacturer +specific USB HID reports.
+Unable to read EDID over USB, even though the HID Report for EDID can be located.
+To set color related VCP feature values, Custom Color mode must be selected. If set to sRGB or Calibrated, the SETVCP command +will appear to succeed, but will have no effect. (In sRGB mode, Brightness can be set, in Calibrated mode it cannot.)
+ +Eizo EV2785
+Reports EDID ad I2c bus address x.50. Does not support DDC/CI (bus address x37).
+Uses USB for monitor control, but uses manufacturer-defined usage pages for communication, i.e. does not support the +USB Monitor Control Class Specification.
+ +Electriq 244MKHDR
+VCP version: 2.2
+Controller manufacturer and model: Realtek 0.1
+Firmware version: 0.1
This is a marketer rebrand of a monitor created by some Chinese company, possibly Meirun. The 3 character manufacturer id "WAM" is not registered.
+The serial number reported is "demoset-1",
+The values reported by the monitor for features x10 (brightness) and x12 (contrast) are not those shown in the OSD. For details, see +ddcutil issue 200: Electriq 24 inch monitor - brightness works but getvcp range doesn't match OSD range.
+Feature x60 (input source) reports invalid value x00 as the current input.
+Feature xCA (OSD/Button Control) reports that the OSD is disabled, even though it is enabled.
+ +Gateway Diamondtron VX920
+VCP version: Unspecified, implies 1.0
+Controller manufacturer and model: Unknown (VCP feature code C8 unsupported)
+Firmware version: Unknown (VCP feature code C9 unsupported)
Hanns G Hi221D
+VCP version: 2.1
+Controller manufacturer: Mstar
+Controller model: mh=x00, ml=x92, sh=x00
+Firmware version: 0.6
All GETVCP requests return a value, whether or not the feature is valid for the monitor. The monitor never reports a feature as unsupported.
+HP LP1965
+VCP version: 2.0
+Controller manufacturer: Undocumented value: x64
+Controller model: mh=xff, ml=xff, sh=x86
+Firmware version: 0.3
+Manufacture year: 2007
Capabilities reports non-standard DDC command x4E.
+Color temperature:
+ color temp increment (feature 0B): 50 deg K
+ color temp request (feature 0C): 70
+ calculated color temp = 3000 + (x0c_val * x0b_val) = 3000 + (70 * 50) = 6500 degrees Kelvin
HP LP2475w
+VCP version: 2.1
+Controller manufacturer: Genesis
+Controller model: mh=xff ml=xff sh=x80
+Firmware version: 0.31
+Manufacture year: 2008
Color temperature:
+ color temp increment (feature 0B): 3000 deg K
+ color temp request (feature 0C): 1
+ calculated color temp = 3000 + (x0c_val * x0b_val) = 3000 + (1 * 3000) = 6000 degrees Kelvin
LUT loading not supported using standard VCP feature codes.
+Implements MCCS over USB as well as I2C. However, the USB implementation appears to be non-standard. It does not conform to the USB Monitor Control Class Specification.
+HP LP2480zx
+VCP version: 2.1
+Controller manufacturer: Genesis
+Controller Model: mh=xff, ml=xff, sh=x80
+Firmware version: 0.139
+Manufacture year: 2008
Heavily reliant on manufacturer specific VCP codes. Most color related features, including loading the internal LUT, are not supported using +standard VCP feature codes.
+Implements MCCS over USB as well as I2C. However, the USB implementation appears to be non-standard. It does not conform to the USB Monitor Control Class Specification.
+Sensible reponses to VCP codes 0B and 0C.
+Capabilities string does not match actual capabilities observed. For example, capaibilites does not include VCP feature code x10, brightness, which is recognized by getvcp and setvcp.
+Values in capabilities string for feature 60 is a mixture of hex and decimal values, i.e.
+ 01 02 03 04 05 07 0C 13 14 15 17 1C
+Should be:
+ 01 02 03 04 05 07 0C 0D 0E 0F 11 ??
+Capabilities string does include cmds() segment listing supported commands, or model() segment listing model.
+HP w2207
+VCP Version: 2.1
+Controller manufacturer: Mstar
+Firmware Version: 3.5
+Manufacture year: 2007
Color temperature increment (feature x0B) and request (feature x0C) result in a color temperature of 13,000 degress Kelvin
+Responds with data to all VCP feature requests, never reports a feature as unsupported
+ +HP ZR2740w
+VCP version: 2.2
+Implements only a few VCP codes.
+VCP feature codes 0B and 0C unsupported.
+ +HP Z27n G2
+ +VCP version: 2.2
+For VCP code 60 (input source), the second DisplayPort input is value 0x13, instead of the standard 0x10. 0x13 is reported accurately as the value to use in capabilities.
+When using VCP code 60 to switch inputs, the value read by GetVCP only updates once the new source has a valid input signal. Until there is a valid signal, GetVCP continues to report the previously selected input.
+ +Iiyama PL2492H
+VCP Version: 2.2 (reported by capabilities string), 2.1 (reported by feature xdf)
+Controller Manufacturer: Connexant
+Firmware version: 0.0
+Manufacture year: 2017
Color temperature increment (feature X0B): 100 degrees Kelvin
+Color temperature request (feature X0C): results in a nonsensical color temperature 1300 (3000 + 100 * 100) degrees Kelvin
Requires that a Save Current Settings packet (command scs) be sent immediately after a Set VCP Feature packet (command setvcp) to actually set the value.
+Never sets the unsupported feature bit in a VCP Feature Reply packet (command getvcp). The capabilities command must be checked to determine if a feature is supported.
+ +Iiyama PL2779Q
+VCP Version: 2.1
+Controller manufacturer: unknown (feature code xC8 unsupported)
+Firmware version: unknown (feature code xC9 unsupported)
+Manufacture year: 2013
Color temperature increment (feature x0B) and request (feature x0C) result in a color temperature of 26,100 degress Kelvin
+Does not include command x02 (VCP Response) or xE3 (Capabilities Reply) in its capabilities string, even though these are supported.
+Responds to several VCP feature not listed in capabilities.
+ +Iiyama PL2792Q
+VCP Version: 2.2 (reported by capabilities string), 2.1 (reported by feature xdf)
+Controller Manufacturer: RealTek (controller number mh=x00, ml=x27, sh=x85)
+Firmware version: 0.0
+Manufacture year: 2020
Color temperature increment (feature X0B): 100 degrees Kelvin
+Color temperature request (feature X0C): results in a nonsensical color temperature of 1300 degrees Kelvin
Requires that a Save Current Settings packet (command scs) be sent immediately after a Set VCP Feature packet (command setvcp) to actually set the value.
+Never sets the unsupported feature bit in a VCP Feature Reply packet (command getvcp). The capabilities command must be checked to determine if a feature is supported.
+Lenovo ThinkVision X1
+VCP Version: 2.1
+Controller manufactuer: Mstar
+Controller Model: mh=0xff, ml=0x16, sh=0x00
+Firmware level 1.0
+Manufacture year: 2016
Color temperature:
+- color temperature increment (feature 0B): 100 deg Kelvin
+- color temperature request (feature 0C): 35
+- calculated color temperature: 3000 + (x0c_val * x0b_val) = 3000 + (35 * 100) = 6500 degrees Kelvin
Brightness (feature x10) cannot be changed when Dynamic Contrast Range (DCR) is enabled (using OSD).
+Per user Janusz Kowalczyk, setting Dynamic Constrast Range and/or Low Blue light in the OSD disables various features in the OSD. +Presumably they cannot be changed by ddcutil either.
+-
+
- Brightness and Contrast may or may not be disabled +
- Color related settings may or may not be disabled +
- Image scaling is disabled +
- DisplayPort version selection is disabled +
Lenovo L22e-20
+VCP Version: 2.0
+Controller Manufacturer: Mstar
+Controller Model: mh=0x00, ml=0x00, sh=0x00
+Firmware level 1.0
+Manuracture year: 2019
EDID has no serial number.
+Color temperature:
+- color temperature increment (x0B): 100 degrees Kelvin
+- color temperature request: (x0C) 0
+- calculated color temperature = 3000 + (0 * 100) = 3000 degrees Kelvin
Brightness and possibly other color related features are disabled when +Dynamic Contrast Range (DCR) is enabled (using OSD).
+LG 22MP48D-P
+VCP Version: 2.1
+Manufacture year: 2016
+Controller manufacturer and model: MStar
+Firmware version: 5.0
Features x0B and x0C are supported. Calculated color temperature = 6500 degrees Kelvin.
+EDID model name is generic "LG IPS FULLHD"
+Never sets the Unsupported Feature bit in replying to a GETVCP request for an unsupported feature. +Instead retuns a success response with all response bytes = 0.
+LG 23EA73
+Never sets the Unsupported Feature bit in replying to a GETVCP request for an unsupported feature. +Instead retuns a success response with all response bytes = 0.
+LG 27MU67
+VCP Version: 2.1
+Manufacture year: 2015
+Controller manufacturer: Mstar
+Controller model: mh=x00, ml=xff, sh=x00
+Firmware version: 3.7
Features X0B and X0C are not supported. Cannot calculate color temperature.
+No serial number in EDID.
+When brightness (VCP feature x10) is changed, it reverts to the original value after approximately 1 second. +The same behavior is seen on Windows using ClickMonitorDDC and softMCCS, so this is clearly a monitor issue. +This problem is not observed for other features.
+LG 27MD5KL UltraFine
+VCP Version: 2.2 (from the capabilities string)
+Manufacture year: 2020
+Controller manufacturer: unknown (feature xc8 unsupported)
+Controller version: unknown (feature xc8 unsupported)
+Firmware version: 3.4
The EDID model name is generic "LG UltraFine".
+This 5K monitor appears to have been built with only Macs in mind. It has no buttons, and no on screen display (OSD).
+Despite an extensive list of features in the capabilities string, getvcp for most returns with the unsupported feature +bit set in the response packet. The only features in the capabilities string that can be read using getvcp are: +0x10 (brightness), xFD (manufacturer reserved), xFF (manufacturer reserved). +In particular, getvcp of feature xDF (VCP version) fails. Per the MCCS specification, this +feature must be supported as of MCCS 2.0.
+The following features unknown to MCCS are not listed in the capabilities string, but return a value for +getvcp: xD1, xD3, xD5, xDD
+This monitor also supports USB access to the Virtual Display Panel, but the only feature supported through this interface is 0x10 (brightness).
+ +LG 29UM69G
+VCP Version: 2.1
+Manufacture year: 2019
+Controller manufacturer: RealTek controller number: mh=0x00, ml=0xff, sh=0x00
+Firmware version: 3.24
+EDID version: 1.3
EDID model name is "LG Ultrawide". No ASCII "serial number". (Binary serial number not checked)
+Malformed capabilities string. (The "cmds" segment is named "UM69cmds")
+ Values ( parsed):
+ 0f: DisplayPort-1
+ 10: DisplayPort-2
+ 11: HDMI-1
+
+ Has 1 HDMI, 1 DisplayPort, 1 USB-C Alt DP
+Users report that it does not support DDC on the DisplayPort input. (See issue LG 29UM69G fails switching input) on github.
+Github user mbastian resported:
+++After more than four months of back and forth with German support I've got this:
+Our Korean software development takes note of reports of this kind, but this does not lead to customer feedback. +Wwe do not see any need for further action here.
+At first they where denying that DDC was even supported, when I've pointed them to the manual and spec sheet then they insisted that it only applied to the OSD. +Finally they escalated it. +I've explained in detail what my problem is, asked if there is a firmware update or an undocumented ddc feature.... and all I got is a not very nice "Don't bother us again!"
+
And Github user AndyKassell reported this response from LG tech support:
+++We have had a response from our Technical Team and they have advised that our monitors do not support DDC-CI officially. Some models are able to issue some commands such as brightness, contrast etc, but if there are issues with this, it would not be considered a fault as it is not guaranteed to work. I apologise for any frustration this causes.
+
LG 27BN88U 27UL850 27GN950-B 29UM69G 34Wk500-P 34WN80C-B 34UM88P 38WN95C
+Users of all these recent LG displays report similar problems with VCP feature X60 (Input Source). +getvcp 60 always returns x00, which is not a valid value. +setvcp 60 flashes the screen, sometimes opens the OSD, never sets the value
+LG 27UD88 29UMS7P
+Users report this monitors do support featrue x60
+LG HDR 4K
+No model name string in EDID. The binary model number is set (x7702 = 30471)
+No ASCII serial number in EDID. Binary serial number is present
+VCP version: 2.1
+Controller manufacturer: MStar (sl=x05)
+Controller Model: mh=x0, ml=xff, sh=x00
+Firmware version: 3.4
+Manufacture year: 2019
Properly sets the Unsupport VCP Code bit in a GETVCP response.
+LG Ultrawide
+VCP version: 2.1
+Controller manufacturer and model: STK
+Firmware version: 0.1
+Manufacture year: 2014
Feature codes are not separated by blanks in the vcp() section of the capabilities string.
+No serial number in the EDID.
+When responding to a Get VCP Feature request, the monitor never sets sets the Result Code field of the VCP Feature Reply to Unsupported VCP Code.
+Instead, it always reports No Error.
+For unsupported VCP codes, all bytes in the response (MH, ML, SH, SL) are set to x00.
Mitsubishi RDT232WLM
+VCP Version: 2.1
+Controller manufacturer and model: unreported (VCP feature code C8 unsupported)
+Firmware version: unreported (VCP feature code C9 unsupported)
+Manufacture year: 2010
DDC/CI communication works for DVI connector. Does not work on HDMI connector.
+DDC/CI communication requires signficant number of retries, and occasionaly fails because of the maximum +number of retries is exceeded.
+Features x0B and X0C are not listed in the capabilities string. The monitor replies +to getvcp requests for these features. +The response to feature X0B (color temperature increment) is 50 degrees Kelvin, which is reasonable. +The response to feature X0C (number of color temperature increments) is 0, resulting in a temperature +of 3000 degrees Kelvin, which is nonsensical.
+Responds to getvcp for feature xA8, which is not defined in the MCCS specification.
+Monoprice Dark Matter 40776
+VCP Version: 2.1
+Controller manufacturer: Mstar
+Controller model: mh=x00, ml=xff, sh=x56
+Firmware version: 0.0
+Manufacture year: 2020
This monitor has 2 HDMI inputs and 2 DisplayPort inputs. The capabilities string reports that VCP feature x60 takes the values +x11, x12, x0f, and x10, which per the MCCS spec are HDMI-1, HDMI-2, DisplayPort-1 and DisplayPort-2 respectively.
+However +the actual values, which are reported by getvcp and settable by setvcp are:
+-
+
- x05 - HDMI-1 +
- x06 - HDMI-2 +
- x07 - DisplayPort-1 +
- x08 - DisplayPort-2 +
A new input source can only be set when ddcutil setvcp 60 is issued from the current input source.
+It is also the case that getvcp and other queries only work when issued on the current input source.
+The ASCII "serial number" in the EDID is blank, and the binary serial number is 0. Consequently, 2 monitors manufactured at the same time will have +identical EDIDs, which will confuse software that depends on the EDID to uniquely identify a display.
+ +NEC LCD3090WQXi
+VCP Version 2.0
+Controller manufacturer and model: unreported (VCP feature code C8 unsupported)
+Firmware version: unreported (VCP feature code C9 unsupported)
+Manufactur year: 2012
Color temperature increment: x0B 100 degress kelvin +Color temperature request 35 -> 3000 + 35*100 = 6500
+ +NEC P241W
+VCP Version 2.0
+Controller manufacturer and model: unreported (VCP feature code C8 unsupported)
+Firmware version: unreported (VCP feature code C9 unsupported)
The capabilities string has 2 additional sets of features, designated vcp_p02 and vcp_p10, in addition to the set specified in +the vcp() field. It also reports the commands xC2, xC4, xC6 and xC8, which are not part of the DDC/CI specification. +Likely these commands are feature request/response pairs for vcp_p02 and vcp_p10.
+Does not use the usual VCP codes (e.g. x16/Red Gain) for color control. +Instead uses the 6 axis color control features x8c..xa0.
+Has an internal hardware LUT, but it is not accessed using the MCCS defined features for LUT mannipulation.
+Uses a proprietary USB for communication, which does not support adhere to the USB Monitor Control Class Specification.
+ +NEC PA241
+VCP Version 2.0
+Controller manufacturer and model: unreported (VCP feature code C8 unsupported)
+Firmware version: unreported (VCP feature code C9 unsupported)
Implements both I2C and USB interfaces.
+Makes heavy use of manufacturer specific VCP feature codes. Also, ddcutil capabilities --verbose reports numerous manufacturer +specific DDC commands The USB interface also makes heavy use of manufacturer specific usage codes.
+Monitor must be set to ??? to allow changes.
+VCP code x0c (Color Temperature Request) returns 0, which is nonsensical.
+Does not use the usual VCP codes (e.g. x16/Red Gain) for color control. +Instead uses the 6 axis color control features x8c..xa0.
+ +Phillips 328P6VU
+VCP Version: 2.2 (capabilities string)
+VCP Version: 3.0 (feature xDF)
+Controller manufacturer: Mstar (sl=0x05), controller number: mh=0xff, ml=0x16, sh=0x00
+Firmware version: 0.0
+Manufacture year: 2019
The EDID contains a binary serial number, but does not contain an ASCII "serial number".
+VCP code 0x0b (Color temperature increment ): 100 degree(s) Kelvin
+When VCP code 0x14 (Select color preset) = User 1 (0x0b):
+VCP code 0x0c (Color temperature request ): 3000 + 35 * (feature 0B color temp increment) degree(s) Kelvin -> 6500 degrees Kelvin
+This is sensible.
Feature xDF (VCP Version) incorrectly reports that the VCP version is 3.0.
+Problems with feature x60 (Input Source):
+- In MCCS version 3.0, feature x60 (Input Source) is of type Table, not Non-Continuous. Because of this getvcp incorrectly
+reads the feature value, and setvcp fails because it expects a value of type Table as input.
+- Feature value x00, which is not listed in any MCCS specification,
+ represents the USB-C connector.
Feature xc0 (Display Usage Time) reports mh=ml=0xff, sh=sl=x00, which is nonsense.
+Phillips BDM3270
+VCP Version: 2.2
+Controller manufacturer: Novatek, model info: mh=xff, ml=xff, sh=x00
+Firmware version: 1.0
+Manufature year: 2016
Color temperature increment (VCP code x0B) = 50 degrees Kelvin (sensible)
+Color temperature request (VCP code x0C) yields a calculated color temperator of 3000+(70*50) = 6500 degrees Kelvin
Phillips BDM4037U
+VCP Version: 2.2
+Controller manufacturer: Realtek (sl=x09), Controller model: mh=x00, ml=x00, sh=x00
+Firmware version 0.1
+Manufacture year: 2016
color temp increment (feature 0B): 100 deg K
+ color temp request (feature 0C): 70 -> 3000+(70*100) = 10000 deg K
DDC communication clean, no need for retries
+Samsung S32D850
+Manufacture year: 2015
+VCP Version: 2.0
+Controller manufacturer: Mstar, controller number: mh=x00, ml=x10, sh=x00
+Firmware version: 0.1
Capabilites request returns a 0 length string.
+Features x0B and X0C are unsupported. Cannot calculate color temperature.
+Has no serial number in EDID
+Samsung Syncmaster 213T
+Does not support DDC.
+Samsung Syncmaster 730B
+VCP version: Unspecified, implies 1.0
+Controller manufacturer and model: Unknown (VCP feature code C8 unsupported)
+Firmware version: Unknown (VCP feature code C9 unsupported)
The capabilities string spcifies the values for non-continuous features in decimal rather than hexadecimal
+VCP feature code
+ +Samsung LC49G95T Odyssey G9
+VCP version reported by capabilitise string: 2.0
+VCP version reported by feature xdf: 2.1
+Controller manufacturer and model: Novatek, model id: mh=xff, ml=0xff, sh=0x00
+Firmware version: 0.0
Two users have reported that DDC/CI does not work over DisplayPort. In both cases they were using the amdgpu +video driver This was true no matter which DisplayPort version was chosen in the OSD. +As of 12/2020, this is not fixed by the most recent monitor firmware update. User razamatan reports +that he was told in Samsung's chat support that DDC/CI is not implemented on DisplayPort.
+The capabilites string reports an unrecognized command code, x4e
+Feature x14 (Color Perset), x06 (Color Temperature Increament) and x06 (Color temperature requrest) appear consistent.
+In one report:
+ VCP code 0x14 (Select color preset ): 7500 K (sl=0x06)
+ Color temperature increment (x0b) = 50 degrees Kelvin
+ Color temperature request (x0c) = 90
+ Requested color temperature = (3000 deg Kelvin) + 90 * (50 degrees Kelvin) = 7500 degrees Kelvin
The monitor has two DisplayPort inputs and one HDMI input. However, the capabilities string reports valid values as being +as x01 - VGA and X03 - DVI-1.
+The following features are not declared in the capabiliteis string but were found by scanning:
+ Feature x52 - Active control
+ Feature xb2 - Flat panel sub-pixel layout
+ Feature xf4 - Manufacturer Specific
+ Feature xfe - Manufacturer Specific
Samsung U32H750
+VCP version reported by capabilities string: 2.1,
+VCP version reported by feature xdf: 2.0
+Controller manufacturer and model: Mstar, model id: mh=x00, ml=0x10, sh=0x00
+Firmware version: 0.1
This monitor is a MCCS disaster area.
+The capabilities string returned by the monitor is malformed. As a result, ddcutil cannot parse the "cmds" field.
+Features x0B and X0C are unsupported. Cannot calculate color temperature.
+No matter what the color mode (x14 Preset, xDC Display Mode) color settings (x16, x18, x1a) cannot be changed. Brightness (x10) and contrast can be changed only in some modes.
+Values in the capabilities string correlate poorly with observed values. +For example, according to the capaiblities string, feature x60 (Input source) has values x11, x12, and x0f, which the MCCS spec defines as HDMI-1, HDMI-2 +and DisplayPort-1 respectively. However, the observed values are x05, x06, and x0f, which the MCCS spec defines as Composite video 1, +Composite video 2, and Displayport respectively.
+ +Viewsonic XG2703-GS
+Manufacture year: 2016
+VCP Version: 2.2
+Controller manufacturer: Manufacturer-designed (sl=xff)
+Firmware version: 1.14
No serial number in EDID
+For unsupported features, sometimes returns a well-formed reply with the "unsupported feature" flag not set. +More often, garbage is returned, resulting in the maximum number of retries.
+Does not support feature x60 (input switching)
+Features X0B and x0C are unsupported. Cannot calculate color temperature.
+ +