Specifications

Programmers Guide TH230/TH230+

238

Endpoint Descriptors

Each endpoint used for an interface has its own descriptor. This descriptor contains the

information required by the host to determine the bandwidth requirements of each

endpoint. An endpoint descriptor is always returned as part of a configuration descriptor.

It cannot be accessed directly with a Get or Set Descriptor request. There is never an

endpoint descriptor for endpoint zero.

Endpoint 1 Descriptor (Interface 0)

This endpoint is used for transferring data from host to printer device.

Offset Field Size Value Description

0 bLength 1 07h Size of this descriptor, in bytes

1 bDescriptorType 1 05h ENDPOINT descriptor type

2 bEndpointAddress 1 81h Endpoint address (IN)

Bit 7 0 = OUT, 1 = IN

Bit 4..6 Reserved, must be 0

Bit 0..3 Endpoint number

3 bmAttributes 1 02h BULK endpoint

4 wMaxPacketSize 2 40h Maximum data transfer size

6 bInterval 1 00h Does not apply to Bulk endpoints

Endpoint 2 Descriptor (Interface 0)

This endpoint is used for transferring data from printer device to host.