Lantronix DSTni-EX manual 14. Address Register, 15. 16- Address Register Definitions

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
FIELD			BDT Page Register										Address Register
				BDT_BA[15:8]						_LSEN						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.

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