Rainbow Electronics AT91CAP9S250A - Manual (Page 886)

886
6264A–CAP–21-May-07
AT91CAP9S500A/AT91CAP9S250A
0 = no effect.
1 = set to force the OpMode signal (UTMI interface) to “10”, to disable the bit-stuffing and the NRZI encoding.
Note: For the Test mode, Test_SE0_NAK (see Universal Serial Bus Specification, Revision 2.0: 7.1.20, Test Mode Sup-
port). Force the device in High Speed mode, and configure a bulk-type endpoint. Do not fill this endpoint for sending NAK
to
the host.
Upon command, a port’s transceiver must enter the High Speed receive mode and remain in that mode until the exit action
is taken. This enables the testing of output impedance, low level output voltage and loading characteristics. In addition,
while in this mode, upstream facing ports (and only upstream facing ports) must respond to any IN token packet with a NAK
handshake (only if the packet CRC is determined to be correct) within the normal allowed device response time. This
enables testing of the device squelch level circuitry and, additionally, provides a general purpose stimulus/response test for
basic functional testing.