Update README.md

README.md

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-# winddcutil
+# winddcutil
+An partial implementation of https://github.com/rockowitz/ddcutil for Windows. Winddcutil can communicate with attached monitors using Display Data Channel/Command Interface (DDC/CI) to query and change monitor state, f.e. to control which input source is displayed.
+
+## Features
+- List attached displays
+- Query display capabilitites string
+- Set VCP feature values
+
+## Usage
+~~~:
+winddcutil <command>
+~~~
+Where command is one of:
+~~~:
+detect
+capabilities <display ID>
+setvcp <display ID> <feature-code> <new-value>
+~~~
+
+## Example
+List available displays:
+~~~:
+C:\>winddcutil detect
+Display 0
+         Name: Dell P2416D(HDMI)
+Display 1
+         Name: Generic PnP Monitor
+~~~
+Show capabilities of display 0:
+<pre>
+C:\>winddcutil capabilities 0
+(prot(monitor)type(LCD)model(P2416D)cmds(01 02 03 07 0C E3 F3)
+vcp(02 04 05 08 10 12 14(05 08 0B 0C) 16 18 1A 52 <b>60(01 11 0F)</b>
+AA(01 02) AC AE B2 B6 C6 C8 C9 D6(01 04 05) DC(00 02 03 05) DF
+E0 E1 E2(00 01 02 04 0E 12 14 19) F0(00 08) F1(01 02) F2 FD)
+mswhql(1)asset_eep(40)mccs_ver(2.1))
+</pre>
+Set VCP feature 96 (0x60) to value 15 (0x0F):
+~~~:
+C:\>winddcutil setvcp 0 96 15
+~~~
+Feature 0x60 is the selected input source. Setting it to 0x0F selects the first display port, at least for this monitor. Available input sources are shown above in bold.
+
+## TODO
+(in no particular order)
+- Parse capabilities string, to create output similar to the original ddcutil.
+- Accept numeric parameters in hexadecimal.
+- Implement more features, such as querying current VCP feature values.