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 it’s 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 reply the error reply ‘0xH’ + ‘yyH’ + data bytes same as
(1).
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
(1)Computer sends the command ‘2xH’, ‘3xH’ or ‘4xH’ + ‘yyH’ + data bytes.
(2)Projector doesn’t understand (1) code.
(3)Projector reply the command ‘00H’ + ‘yyH’
The example of data error
(1)Computer sends the command ‘2xH’, ‘3xH’ or ‘4xH’ + ‘yyH’ + data bytes.
(2)Projector doesn’t understand (1) data bytes.
(3)Projector reply the command ‘0xH’ + ‘yyH’ + data bytes same as (1)
The example of framing error
(1)Projector detect framing error.
(2)Projector changes to 1200bps 7N1 if it doesn’t 1200bps 7N1.
(3)Projector replys ’70H’ + ’70H’ 10 times, every 1 second.
(4)When projector receives ’70H’ + ’70H’, it replys ’12H’ + ’03H’ + ’01H’ + ’00H’.
The interval of command bytes and data bytes
(1)The interval of bytes exceeds 500mS.
(2)Projector replys ’70H’ + ’70H’.
(3)Projector wait 1 second for the computer’s any command.
(4)If there is no command from the computer, projector treat as framing error.
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.
• The interval of Reply code and other codes must be over 40mS.
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