Hatteland Display 13 inch - HD 13T21 STD (Widescreen) - Manual (Page 5)

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DOC101681-1- rev.2
5
8 and 13" DIS DDC Control
All intellectual properties belongs to Hatteland Display AS
3.
Communicate List
Define an I
2
C ™ based protocol which operates over the DDC channel to provide interactive
control of a display and, optional associated devices. Communicate are divided into two parts.
One is the standard and other is a manufacture specific.
3.1. DDC/CI communicate flowchart description
 Set VCP Feature
Send the adjustment data from host to the display corresponding to a specified VCP.
6E  Destination address
51  Source address
84  Length
03  Set VCP Feature COMMAND
CP  VCP opcode
SH  High byte
SL  Low byte
CK  DDC/CI checksum
Interval:
The host should wait at least 50ms to ensure next message is received
by the display.
 Get VCP Feature and VCP Feature Reply
1. Send a request from host to the display for the adjustment data corresponding to a
specified
VCP code.
2. Wait 50ms
3. Receive the current setting data from the display to the host for the adjustment specified
by
the VCP code.
6E  Destination address
51  Source address
82  Length
01  Get VCP Feature COMMAND
CP  VCP opcode
CK  DDC/CI checksum
Interval:
The host should wait at least 50ms to
ensure next message is received by the
display.
Host Display
[S] 6E [W] 51 84 03 CP SH SL CK [P]
Display
decodes and
changes the
setting
Host Display
[S] 6E [W] 51 84 01 CP CK [P]
Display
decodes and
issues the reply
message
Host
[S] 6F [R] 6E 88 02 RC CP TP MH ML SH SL CK [P]