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ADM5120
Register Description
31:0
Reserved
Not
Applicable
4.6.5 Host General Control, offset 0x10
Bits
Type Name
Description
Initial value
1:0 R/W
BUS_STATE
USB bus state
00: USB reset state.
01: USB resume state.
10: USB operational state.
11: USB suspend state.
A transition to USB operational state will cause the SOF
generation to start 1 ms later.
2’b00
2 R/W
DMA_EN
USB host DMA enable
This bit enables the host controller DMA functionality.
When enable the DMA will start to fetch the descriptor
for processing.
0
31:3 RO
Reserved
Not
Applicable
0
4.6.6 Reserved, offset 0x14
Bits
Type Name
Description
Initial value
31:0
Reserved
Not
Applicable
4.6.7 SOF Frame interval, offset 0x18
Bits
Type Name
Description
Initial value
13:0 R/W
FM_INTERVAL
Frame interval
This specifies the interval between two consecutive
SOFs in bit times. The nominal value is set to be
11,999. Software should store the current value of this
field before resetting HC.
2EDFh
15:14 RO Reserved
Not
Applicable
0
30:16 R/W FSLargestDataPac
ket
FSLargestDataPacket
This field specifies a value which is loaded into the
Largest Data Packet Counter at the beginning of each
frame. The counter value represents the largest amount
of data in bits which can be sent or received by the HC
in a single transaction at any given time without causing
scheduling overrun. The field value is calculated by the
software.
0
31 RO
FM_INTERVAL_
TOG
FrameIntervalToggle
Software toggles this bit whenever it loads a new value
to FM_INTERVAL.
0
ADMtek Inc.
4-29