Siemens C541U User Manual page 97

Table 6-6
Bitfield Definition of USB Configuration Block
Bitfield
EPNum
EPType
EPDir
EPPackSize
Semiconductor Group
Description
This 3-bit field specifies the number of the endpoint (0-4) for which the actual
configuration byte block is valid. This 3-bit field must be referenced in byte 0
and byte 3 of a configuration byte block.
This 2-bit field defines the type of the endpoint
00 : Control endpoint
01 : Isochronous endpoint
10 : Bulk endpoint
11 : Interrupt endpoint
Endpoint 0 must be setup for control endpoint-
This bit defines the direction of the endpoint
0 : Out (packets to be transferred from Host to CPU)
1 : In (packets to be transferred from CPU to Host)
This 10-bit field defines the maximum packet size to be transferred to this
endpoint within the range from zero up to 1023 bytes. The configuration of
EPPackSize has to be in harmony to the USB specification.
On-Chip Peripheral Components
6-52
C541U
1999-04-01