Connection to the control signal terminal (continued)
The procedure of getting the Projector status
(1)Computer sends the command '20H'+'yyH' to Projector.
(2)Projector reply the command '1xH'+'yyH'+data bytes.
The procedure of setting the Projector status
(1)Computer sends the command '3xH'+'yyH'+data bytes.
(2)Projector changes itÕs status.
(3)Projector reply the command '1xH'+'yyH'+data bytes which indicate status.
Caution | ∙ (3) data bytes is not always same as (1) data bytes. If projector cannot realize the status of (1) | |
data bytes, projector set the proper status and reply this new setting data bytes or projector | ||
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| reply the error reply '0xH'+'yyH'+data bytes same as (1). |
∙When only power control (POWER COMMAND) is performed, it takes about 2~80 seconds between sending set code and receiving answering code.
The procedure of default setting the Projector status
(1)Computer sends the command '40H'+'yyH'
(2)Projector changes it's status to default setting.
(3)Projector reply the command '1xH'+'yyH'+data bytes which indicate default.
Caution If projector replys '4Dh', (before command code, etc.) computer ignores '4Dh'
The example of command error
When projector cannot accept command from PC, error code '00H'+'yyH' is sent back.
(in a case when command code '2xH', '3xH' or '4xH'+'yyH'+data is sent from PC to projector)
The example of data error
When projector cannot accept command from PC, error code with data '00H'+'yyH'+data is sent back as it
is. (in a case when command code '2xH', '3xH' or '4xH'+'yyH'+data is sent from PC to projector)
When data is longer than required data code length, projector ignores excess data code.
When data is shorter than required data code length, projector sends back error code shown above.
The example of framing error
After setting to 1200bps 7N1, projector sends error code '70H'+'70H' up to 10 times at intervals of 1 second
until any answer is received. When projector receives framing error code ('70H'+'70H'),
'12H'+'03H'+'03H'+'10H' is sent with 1200 bps 7N1.
The interval of command bytes and data bytes
After command code '2xH', '3xH' or '4xH' is sent from PC, if command or data is not sent within 500ms,
projector sends back error command '70H'+70H'. If no answer is sent within 1 second from that time,
framing error is assumed.
Caution | ∙ The interval of command bytes and data bytes must be over 1mS and under 500mS. If it is | |
under 1mS, it may be treat as framing error. | ||
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∙After projector has sent back answer code, when next command is to be sent from PC, allow for an interval of 40ms or more between answer code and other code.
ENGLISH
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