Required USB Parameter Block Fields
All calls to the USL that require a
USBPB
parameter block must supply the these fields:
-
pbLength
-
Length of the
USBPB
parameter block, including any client additions
-
pbVersion
-
Version number of
USBPB
in binary-coded decimal, currently 1.1, initialize to
kUSBCurrentPBVersion
or
kUSBIsocPBVersion
for isochronous call support. See
Changes In Mac OS USB Version 1.1
for additional information about how it use the isochronous variant of the USB parameter block.
-
usbCompletion
-
Completion routine
-
usbRefcon
-
For client use
-
usbFlags
-
Unless otherwise specified in the function description, should be set to 0
The listed fields may not explicitly be referenced in all the call descriptions in this document, but they are required.
© 1998 Apple Computer, Inc. – (Last Updated 23 Nov 98)Previous | Back Up One Level | Next |
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