USB CONFIGURATION
The AN2720 supports a single configuration, with one interface consisting of the five alternate
settings shown in Table 1.
Table 1. AN2720 endpoints and interface alternate settings
Endpoints
Setting 0 Setting 1
Setting 2
Control
intrpt (1mS)
Bulk
Setting 3
Test
Mode
Setting 4
Test
Mode
ep0 (8 Bytes)
Control
X
Test
ep1in (8 Bytes)
ep2in (64 Bytes)
ep2out (64 Bytes)
ep3in (64 Bytes)
ep3out (64 Bytes)
Mode
Bulk
Bulk
X
Bulk
Bulk
Bulk
X
Alternate setting 0 is intended to consume no fixed USB bandwidth, ensuring that the AN2720
will always be enumerated on the USB bus. Alternate setting 2 uses the USB bandwidth more
efficiently, employing an interrupt endpoint for status notification.
Alternate settings 1, 3 and 4 are diagnostic modes reserved by Cypress. Do not use these modes.
AN2720 Data Sheet Version 1.0
06/07/00
Page 6
CYPRESS [ CYPRESS ]
