Texas Instruments TMS320DM357 - Manual (Page 118)

4.55 Register to Enable the USB 2.0 Test Modes (TESTMODE)
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The Register to Enable the USB 2.0 Test Modes (TESTMODE) is shown in Figure 70 and described in
Table 71 .
Figure 70. Register to Enable the USB 2.0 Test Modes (TESTMODE)
7 6 5 4 3 2 1 0
FORCE_HOST FIFO_ACCESS FORCE_FS FORCE_HS TEST_PACKET TEST_K TEST_J TEST_SE0_NAK
R/W-0 W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0
LEGEND: R/W = Read/Write; W = Write only; -n = value after reset
Table 71. Register to Enable the USB 2.0 Test Modes (TESTMODE) Field Descriptions
Bit Field Value Description
7 FORCE_HOST 0-1 Set this bit to forcibly put the USB controller into Host mode when SESSION bit is set,
regardless of whether it is connected to any peripheral. The controller remains in Host mode
until the Session bit is cleared, even if a device is disconnected. And if the FORCE_HOST but
remains set, it will re-enter Host mode next time the SESSION bit is set. The operating speed is
determined using the FORCE_HS and FORCE_FS bits.
6 FIFO_ACCESS 0-1 Set this bit to transfer the packet in EP0 Tx FIFO to EP0 Receive FIFO. It is cleared
automatically.
5 FORCE_FS 0-1 Set this bit to force the USB controller into full-speed mode when it receives a USB reset.
4 FORCE_HS 0-1 Set this bit to force the USB controller into high-speed mode when it receives a USB reset.
3 TEST_PACKET 0-1 Set this bit to enter the Test_Packet test mode. In this mode, the USB controller repetitively
transmits a 53-byte test packet on the bus, the form of which is defined in the Universal Serial
Bus Specification Revision 2.0.
Note: The test packet has a fixed format and must be loaded into the Endpoint 0 FIFO before
the test mode is entered.
2 TEST_K 0-1 Set this bit to enter the Test_K test mode. In this mode, the USB controller transmits a
continuous K on the bus.
1 TEST_J 0-1 Set this bit to enter the Test_J test mode. In this mode, the USB controller transmits a
continuous J on the bus.
0 TEST_SE0_NAK 0-1 Set this bit to enter the Test_SE0_NAK test mode. In this mode, the USB controller remains in
high-speed mode, but responds to any valid IN token with a NAK.
Universal Serial Bus (USB) Controller 118 SPRUGH3 – November 2008
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