SPECIAL
FEA
TURES
47
206-3825
Example;
To determine the status of a unit that was turned on
and viewing channel 3, with a good signal, at a vol-
ume of 29 decimal the controller would issue the
following command string:
●
B0B0
To which the TV would return the following string
after disabling the front panel and IR control if they
are currently active:
●
ABDD038B
AB : It is the start of the command and signifies a
data return command.
DD : It is the data byte.
03 : It is the second data byte.
8B : It is the checksum calculated by adding “AB” +
“DD” to get “8B” after truncating the resulting
“18B”.
The first data byte DD hex breaks down to the fol-
lowing 8 bit word (MSB) 11011101 (LSB) and the first
two bits can be read as power on, signal status good,
the remaining bits yield 29 decimal as the volume
setting.
The second data byte 03, hex breaks down to RF
channel 3.
08. Poll/Front panel-IR Lock Out
- This command is used to determine the status
of the TV and set the front panel keys and
infrared (IR) control. The command is issued
to the TV and the TV will return the status of
the unit as described below. If the command is
issued in the form of “A0” the front panel keys
and IR control are active and remain that way
until a subsequent “B0” command is issued. If
the command is issued in the form of “B0” the
front panel keys and IR control are disabled
and remain that way until a subsequent “A0”
command is issued. In either form of the com-
mand the TV responds with the status read
back information. A checksum equal to the
command is transmitted.
A0A0 or B0B0
09. Status Read Back
- This command allows the controller to obtain
the status of the TV. The values reported are
volume setting, current channel/input, and
input signal strength status. The status read
back command is initiated by issuing a stan-
dard poll command;
B0 or A0 : It is the start of the command and sig-
nifies that the TV should return the status
of the unit to the controller. “B0” is used
when the front panel is to be locked out or
to remain locked out and “A0” is used
when the status is to be returned and the
front panel is to be unlocked or remain
unlocked. No data bytes are sent.
Upon receipt of the poll command the TV
will return the status in the form of the fol-
lowing command:
AB : It is the start of the command and signi-
fies a data return command.
WW : It is the second data byte.
YY : It is the checksum calculated by adding
the previous bytes together and truncat-
ing.
- Data byte 1 (the first data byte received)
- The two 8 bit data bytes are organized as
follows:
- Data byte 2 (the second data byte received)
B0 or A0
ABWWXXYY
Channel
Number Source
1 to 125
Traditional RF
131
Rear composite Video Input
132
Rear S-Video Input
133
Front RGB Video Input
(Not used on current LCD design)
134
Rear RGB Video Input
135
Not used
(Reserved for Scan Card Products)
136
Rear Y, Pb, Pr Component Input
137
Front S-Video
138
Not Used (Reserved for internal
Y, Pb, Pr Video Input)
139
Not Used (Reserved for internal
S-Video Input)
Bit
Description
0-5
Volume level in hex,
(00=minimum, 3F=maximum)
6
Signal status (1=Good, 0=Bad)
7
Power Status (1= On, 0=Off)
Bit
Description
0-7
Channel number,
00-FF hex
