Information

40.4.16 BDT Page Register 1 (USBx_BDTPAGE1)
The Buffer Descriptor Table Page Register 1 provides address bits 15 through 9 of the
base address where the current Buffer Descriptor Table (BDT) resides in system memory.
The 32-bit BDT Base Address is always aligned on 512-byte boundaries, so bits 8
through 0 of the base address are always taken as zero.
Addresses: USB0_BDTPAGE1 is 4007_2000h base + 9Ch offset = 4007_209Ch
Bit 7 6 5 4 3 2 1 0
Read
BDTBA
0
Write
Reset
0 0 0 0 0 0 0 0
USBx_BDTPAGE1 field descriptions
Field Description
7–1
BDTBA
This field provides address bits 15 through 9 of the BDT base address.
0
Reserved
This read-only field is reserved and always has the value zero.
40.4.17 Frame Number Register Low (USBx_FRMNUML)
The Frame Number Register (Low and High) contains an 11-bit value used to compute
the address where the current Buffer Descriptor Table (BDT) resides in system memory.
Addresses: USB0_FRMNUML is 4007_2000h base + A0h offset = 4007_20A0h
Bit 7 6 5 4 3 2 1 0
Read
FRM[7:0]
Write
Reset
0 0 0 0 0 0 0 0
USBx_FRMNUML field descriptions
Field Description
7–0
FRM[7:0]
This 8-bit field and the 3-bit field in the Frame Number Register High are used to compute the address
where the current Buffer Descriptor Table (BDT) resides in system memory.
Chapter 40 Universal Serial Bus OTG Controller (USBOTG)
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
Freescale Semiconductor, Inc. 909