3M™ MicroTouch™ Controller EX Dual Mode Reference Guide
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3M Touch Systems, Inc. Proprietary Information – TSD-40848A
Sending Commands to the Controller
Table 5. General Format for Vendor Requests
Offset
Field
Size
Value
Description
0
bmRequestType 1
d1000000 Characteristics of request [dir, type, recipient]
D7: Data Transfer Direction
0 = Host-to-device
1 = Device-to-host
D6… 5 Type
0 = Standard
1 = Class
2 = Vendor
3 = Reserved
D4…0 Recipient
0 = Device
1 = Interface
2 = Endpoint
3 = Other
4…31 = Reserved
1
bRequest
1
0xXX
Specific request [our command number]
2
wValue
2
0xXXXX
Used to specify command parameters
4
wIndex
2
0xXXXX
Used to specify command parameters
6
wLength
2
0xXXXX
Number of bytes to transfer
The Type field should be set to Vendor (0x10). The Recipient field should be set to
Device. The Direction field depends on the command.
Receiving Reports from the Controller
Four reports can be sent from the controller to the host. These reports fit into two
categories: those sent immediately in response to a host request (synchronous) and those
sent when updates to the data they contain become available (asynchronous).
Synchronous reports:
•
Report 4
Parameter Data
•
Report 6
Status
•
Report 12
Controller ID
Asynchronous reports:
•
Report 1
Coordinate Data
Some possible reasons for a command failure include:
•
The command was not formatted correctly.
•
The system parameters were not set up to allow command execution.
•
The controller does not support the command.
