Lantronix DSTni-EX - Manual (Page 53)

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Address Register
The Address register contains the unique USB address that the USB decodes in peripheral
mode (HOST_MODE_EN=0). In host mode (HOST_MODE_EN=1), the USB transmits this
address with a TOKEN packet. This enables the USB to uniquely address any USB peripheral.
In either mode the USB_EN bit in the Control register must be set. The register resets to 00h
after the reset input activates or the USB decodes a USB reset signal. This action initializes the
address register to decode address 00h, in keeping with the USB specification.
Note: The Buffer Descriptor Table Page register contains part of the 24 bit address used to
compute the address where the current Buffer Descriptor Table (BDT) resides in system
memory.
Table 4-14. Address Register
BIT 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
OFFSET 06h
BDT Page Register Address Register
FIELD
BDT_BA[15:8]
LS_EN
ADDR[6:0]
RESET 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
RW R R R R R R R R R R R R R R R R
Table 4-15. 16- Address Register Definitions
Bits Field Name Description
15:8 BDT_BA BDT Base Address
This 8-bit value is the most-significant bits of the BDT base address, which
defines where the Buffer Descriptor Table resides at in system memory. The 16-
bit BDT base address is always aligned on 256-byte boundaries in memory.
7 LSEN Low Speed Enable (valid for host mode only)
Tell the USB that the next token command written to the token register must be
performed at low speed. This lets the USB perform the necessary preamble
required for low-speed data transmissions.
6:0 ADDR[6:0] USB Address
Defines the USB address that the USB decodes in peripheral mode or transmits
in host mode.