Mimio MimioDisplay 550T, Руководство по установке

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Appendix B: RS-232 Control
This section describes the MimioDisplay communication connection and protocol via RS-232.
Data Format
Data will be transferred serially, according to RS-232 protocol, using the following settings. Connections are as
specified in the RS-232 standard. The recommended data rate is 9600 baud.
Baud Rates 9600
Data Bits 8
Stop Bits 1
Parity No
Data Structure
Note
•
All numbers shown in the protocol description are in string, unless indicated otherwise.
•
Percentages are shown in decimals.
General Command Form
•
STX. The first character is the standard Start of Text (STX) character ‘S.’
•
Address. The second character is the device address. If a device does not support addressing, the second
character should be 0, or 9 to act as the global address.
•
Type. The third character is the command type. There are four types of commands:
o
Command0
o
Ack1
o
Nak2 (option)
o
Notification 3 (option)
•
Property ID. The four and fifth characters are the property identifier. By using one byte, we have 256.
•
Data Length. The sixth character is the number of characters in the parameter data section.
•
Data. Following the sixth character is the parameter data section, which is as many characters long as the sixth
character indicates. If the sixth character is 00 (as with the Reset command, for example), then there are no
characters in the parameter section. This parameter section contains the value (hexadecimal) for the property.
•
ETX. The last character is the standard End of Text (ETX) ‘EN.’
Sample:
STX Address Type Property
ID Length Data ETX
S 0 0 0 1 1 1 EN
In this example (Power On to everything), the Address character is 0, which is the global address for all devices
connected to the serial port. The Type character is 0 to indicate the transmission is a command. The Property ID
characters indicate a property identifier of 1, which, in this protocol, is the value for power. The Length character is 1,
which indicates that there is one character of data associated with this command. The Data has a value of 1, which is
the value for ON. The ETX is command End code.
3-6-4 Command code
3-6-4-1 User Command
In the following samples, the global device address of 0 is used.
The numbers in brackets are the string value that is associated with the property or the property value.
Note that these values are used in the command string.
For the properties that support ranges such as brightness and volume, examples are provided for low and high.