Sharp PN-U423 - Manual (Page 31)

31
E
Controlling the Monitor with a PC (RS-232C)
n Response code format
When a command has been executed correctly
O K
Return code
(0D H , 0A H )
A response is returned after a command is executed.
* If an ID number has been assigned
O K SPC 0 0 1
ID number of responding monitor
Space (20 H )
Return code
(0D H , 0A H )
When a command has not been executed
R R E
Return code
(0D H , 0A H )
* If an ID number has been assigned
R R E SPC 0 0 1
ID number
Space (20 H ) Return code
(0D
H
, 0A
H
)
TIPS
• “ERR” is returned when there is no relevant command or
when the command cannot be used in the current state of
the monitor.
• If communication has not been established for reasons
such as a bad connection between the PC and monitor,
nothing is returned (not even ERR).
• “ERR” may be returned when a command cannot be
received correctly due to interference from the surrounding
environment.
Please ensure that the system or software retries the
command if this occurs.
• If no monitor has been assigned the designated ID number
(e.g. if the command IDSL0002 is used, but no monitor
with ID number: 2 is found), no response is returned.
If execution of the command is taking some time
I W T A
Return code
(0D
H
, 0A
H
)
When the following commands are used, “WAIT” is returned.
In this case, a value will be returned if you wait a while. Do not
send any command during this period.
No ID number is attached to WAIT response.
• Commands which return WAIT:
1. When repeater control is used
2. When an IDSL or IDLK command is used
3. When one of the following commands is used: RSET,
INPS, ASNC, WIDE, PXSL, POWR, MWIN, MWIP,
EMHV, EPHV, ESHV, ENLG, BOMD
n Communication interval
• After OK or ERR is returned, you must send the following
commands.
To set a timeout for the command response, specify 10
seconds or longer.
When connecting multiple monitors in a daisy chain, set the
timeout to at least the product of the monitor’s position from
the computer multiplied by 10 seconds.
Example) 3rd monitor from computer: 30 seconds or longer.
• Provide an interval of 100 ms or more between the
command response and the transmission of the next
command.
VOLM0020
OK
INPS0001
WAIT
OK
Interval of 100 ms or more
TIPS
• When executing ALL RESET, set the timeout period to 30
seconds or longer.
• When turning the power on while the POWER ON DELAY
function is in use, set the timeout period to the POWER ON
DELAY period + 10 seconds or longer.
Advanced operation
This section explains commands for daisy chain connection.
The basic communication procedure is the same as in the
“One-to-one connection with a PC” section.
n ID numbers
You can assign a unique ID number to each monitor (see
page 23). This allows you to control a particular monitor in a
daisy chain of monitors.
You can assign ID numbers either from the menu screen or
from the PC using RS-232 cable.
[Example]
ID number: 1 ID number: 2 ID number: 3 ID number: 4
If monitors are connected as shown above, you can
execute commands like “Set the volume of the monitor with
ID 4 to 20”.
When designating ID numbers for a set of monitors linked in a
daisy chain, you should basically avoid any duplication of ID
numbers.
ID numbers do not have to be assigned in ascending order
starting from the PC. They can also be connected as shown
below.
[Example]
ID number: 3 ID number: 2 ID number: 4 ID number: 1