Christie Boxer 4K, Техническое описание

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Message
requirement Description
• Full Acknowledgments—Insert a hash (#) character just after the start code bracket.
This returns the message sent, as a reply.
This is a quick way to confirm success with set messages and is useful with long distance
communication links or where the projectors and/or images are not visible from the
controller. Acknowledgments can also be a type of flow control.
Checksums For maximum message integrity, add a checksum character ampersand (&) just after the
start code bracket. You must also include the correct checksum total (0-255) just before
the end code bracket. Make sure to add a space before the calculated checksum to
separate it from the last data parameter:
The checksum is the low byte of the sum of the ASCII values of all characters between the
start bracket and the beginning of the checksum, but not including either. It does include
the space in front of the checksum.
Calculate the checksum for the above set contrast to 64 command as follows:
CHECKSUM EXAMPLE = & + c + o + n + 6 + 4 + ‘space’
= 26h+63h +6Fh +6E h +36h +$34h +$20h
= 01F0h
= F0h when only the low byte is used
= 240
Boxer 4K collects all of the message bytes as defined in the first byte of the message, then
creates its own checksum value for comparison with the checksum included in the
controller’s message. If the values match, the message is considered to have been
correctly received; otherwise, the message is discarded.
Note the following:
• h indicates a hex number.
• If a request message has a checksum, so does the reply.
• If using both acknowledge and checksum, either character can occur first.
Error messages
If a command cannot be performed, a descriptive error identifying the problem appears.
For example, the following message indicates a syntax error:
(ITP) - (65535 00000 ERR00005 "ITP: Too Few Parameters")
Descriptive error
The following error codes indicate a problem if a command cannot be performed.
Error code Description Error code Description
3 Invalid parameter 105 Disabled control
4 Too many parameters 106 Invalid language
5 Too few parameters 107 Exceeded list size
Communicating with Boxer 4K
Boxer 4K Serial API Commands Technical Reference 11
020-101697-05 Rev. 1 (07-2017)
Copyright
©
2017 Christie Digital Systems USA Inc. All rights reserved.