42.4.16 BDT Page register 1 (USBx_BDTPAGE1)
Provides address bits 15 through 9 of the base address where the current Buffer
Descriptor Table (BDT) resides in system memory. See
bit BDT Base Address is always aligned on 512-byte boundaries, so bits 8 through 0 of
the base address are always zero.
Address: 4007_2000h base + 9Ch offset = 4007_209Ch
Bit
7
6
5
4
3
2
1
0
Read
Write
Reset
0
0
0
0
0
0
0
0
USBx_BDTPAGE1 field descriptions
Field
Description
7–1
BDTBA
Provides address bits 15 through 9 of the BDT base address.
0
Reserved
This field is reserved.
This read-only field is reserved and always has the value 0.
42.4.17 Frame Number register Low (USBx_FRMNUML)
The Frame Number registers (low and high) contain the 11-bit frame number. These
registers are updated with the current frame number whenever a SOF TOKEN is
received.
Address: 4007_2000h base + A0h offset = 4007_20A0h
Bit
7
6
5
4
3
2
1
0
Read
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 42 Universal Serial Bus Full Speed OTG Controller (USBFSOTG)
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
Freescale Semiconductor, Inc.
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