3M MicroTouch EX111, Справочное руководство

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28 3M™ MicroTouch™ Controller EX USB Reference Guide
3M Touch Systems, Inc. Proprietary Information -- 29489v05
Response
The parameter data is sent to the host in a Parameter Data report. All parameter data is
treated as if it were stored as bytes. This means that multi-byte values will be sent MSB
first.
If the command cannot be processed, the device stalls endpoint 0. The command cannot
be processed if the parameter number is not valid. It cannot be processed if less than 4
bytes (wLength) are requested. It cannot be processed if more data is requested than is
contained in the parameter.
Parameter Data Report 4
This report is sent in response to any request for parameter data. All parameter data is
treated as if it were stored as bytes in the order that it is stored in memory. This means
that multi-byte values will be sent MSB first.
Table 20. Parameter Data Report
Offset Field Size Value Description
0 Report ID 1 0x04 Report ID number
1 Data size 2 0xXXXX Amount of data to follow
3 Data bytes Data Size 0xXX Data bytes
Data size – the number of data bytes to follow.
Data byte – At least 1 data byte will follow when data size is greater than zero. The
number of data bytes returned by this report is limited by the “Max Param Write” value
returned by the Controller ID report. The contents of this data section are dependent on
which parameter is being accessed.