ViewSonic Vt2756-l Manual

32
ProblemPossible Solution
Remote control unit does 
not operate • 
Make sure the batteries are inserted correctly.
•  Batteries could be weak or dead. Replace with new batteries.
•  Check if there is a fluorescent light illuminated near the remote 
control sensor.
•  The path of the remote control beam may be blocked. Make 
sure the path is clear and that the remote control is aimed at the 
remote control sensor on the TV.
•  Press 
 on the remote control to see if you can turn on the TV.
•  Press MENU...

33
Specifications
ModelVT2756-LVT2406-L
LCD
(LED Backlight)Screen Size
27-inch Full HD 60Hz 24-inch Full HD 60Hz
Aspect Ratio 16:9 16:9
Television System ATSC / 64 & 256 QAM / 
NTSC-MATSC / 64 & 256 QAM / NTSC-M
Program Coverage VHF : 02~13              UHF : 14~69                  DTV : 02-69
CATV : 01~125          CADTV : 01~135
Input signal RGBRGB analog (0.7/1.0 Vp-p, 75 ohms) Separate Sync,
fh: 31.5-67.5 kHz, fv:59.94-60 Hz
RF TV system Antenna / NTSC+ATSC, TV cable system /
CATV+Digital cable
Video...

34
RS232 Protocol
1. IntroductionThis document describes the hardware interface spec and software protoco\
ls of RS232 interface 
communication between Viewsonic Commercial Display and PC or other control unit with RS232 
protocol.
The protocol divide into three sections:
• Set-Function
• Get-Function
• Remote control pass-through mode
h In below document, “PC” will represents all the control units tha\
t can sent or receive the RS232 protocol command.
2. Description 2.1 Hardware specification
Viewsonic...

35
3. Protocol3.1 Set-Function Listing
The PC can control the TV Monitor for specific actions. The Set-Function command allows you to
control the TV behavior in a remote sit through the RS232 port. The Set-Function packet format
consists of 9 bytes.
Set-Function description:
Length: Total Byte of Message excluding “CR”
TV ID: Identification for each of TV
If we want to set all TV settings, TV ID can use “99” to achieve, and
it will not have Reply command on this function.
The TV ID can be set via the OSD...

36
Reply (Hex Format)
Name
LengthIDCommand 
Type CR
Hex
0x340x30
0x320x2B0x0D
Example2: Set Brightness as 176 for TV-02 and this command is NOT valid.
Send (Hex Format)
Name LengthIDCommand
Type Command
Value1Value2Value3 CR
Hex
0x380x30
0x320x730x240x310x370x360x0D
Reply (Hex Format)
Name LengthIDCommand
Type CR
Hex
0x340x30
0x320x2D0x0D
Set-function table
Set  
Function Length
IDCommand 
Type (ASCII) Command
Value Range  
(Three ASCII bytes) Comments
Code (ASCII) Code (Hex)
Power on/
off(standby) 8...

37
OSD 
language8
s232000: English
001: French
002: Spanish Extend the value for
more supported
languages
Power lock 8s434000 : Unlock
001 : Lock
Volume 8s535000 ~ 100
Mute 8s636000: OFF
001: ON (mute)
Button lock 8s838000: Unlock
001: Lock
TV channel
(DTV) 8
s< 3C 
For -0:
001~999
A00~F99
(1000~1599)
For -k:
1
st and 2nd char are 
same as -0
3
th char is
CHAR[ ASC(3th
digi)+ k x 10 ] It’s channel OSD
number but not
frequency number.
TV channel
(ATV) 8
s= 3D001~999
Menu lock 8s> 3E000: Unlock
001: Lock...

38
[NOTE]
1. Behavior at lock modes
Lock ModeBehavior
Button Lock 1. Lock all buttons of front panel and RCU, except for “Power”
2. All the SET functions should be workable via RS32, even the ones with
according hot key in RCU like Mute,…etc.
MENU Lock 1. Lock “MENU’ key of front panel and RCU
2. The Factory and Hospitality modes should not be blocked for the 
model
using MENU-combined key to enter these two modes. Alternative 
approach
will be indicated separately if any limitation by model.
POWER Lock...

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Get-Function format:
 
Send: (Command Type= “g”)
Name LengthIDCommand
Type Command
Value1Value2Value3 CR
Byte Count 1 Byte2 Byte 1 Byte 1 Byte1 Byte1 Byte1 Byte1 Byte
Bytes 
order 1
2~3 4 56789
Reply: (Command Type= “r” or “-”) 
If the Command is valid, Command Type = “r”
Name LengthIDCommand
Type Command
Value1Value2Value3 CR
Byte Count 1 Byte2 Byte 1 Byte 1 Byte1 Byte1 Byte1 Byte1 Byte
Bytes 
order 1
2~3 4 56789
If the Command is Not valid, Command Type= “-”
Name LengthIDCommand
Type CR
Byte Count 1...

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Reply (Hex Format)
NameLengthIDCommand
Type CR
Hex
0x340x30
0x350x2D0x0D
Get-function table
Get 
Function Length
IDCommand 
Type Command
Response Range  
(Three ASCII  bytes) Comments
Code (ASCII) Code (Hex)
Get-Contrast 8ga61000 ~ 100
Get-Brightness 8gb62000 ~ 100
Get-Sharpness 8gc63000 ~ 100
Get-Color 8gd64000 ~ 100
Get-Tint 8ge65000 ~ 100
Get-Volume 8gf66000 ~ 100
Get-Mute 8gg67000: Off
001: On (muted)
Get-Input select 8gj6A000~  See Set-function 
table
Get-Power
status: ON/
STBY 8
gl6C001: ON
000:...

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IR Pass Through-Function format
 
Reply: (Command Type= “p”)
Name LengthIDCommand
Type RCU Code1
(MSB) RCU Code2
(LSB) CR
Byte Count 1 Byte2 Byte 1 Byte 1 Byte 1 Byte1 Byte
Bytes 
order 1
2~3 4 5 67
Example1:  Remote Control pass-through when “VOL+” key is pressed \
for TV-05 
Reply (Hex Format)
Name LengthIDCommand
Type RCU 
Code1 (MSB) RCU 
Code2 (LSB) CR
Hex
0x360x30
0x350x700x310x300x0D
Key Code (HEX)
1 01
2 02
3 03
4 04
5 05
6 06
7 07
8 08
9 09
0 0A
- 0B
RECALL (LAST) 0C
0D
0E
ASPECT (ZOOM) 0F...