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CONNECT
Meaning:
Connect to USB.
Location:
USBCTL.3
Set:
The CPU sets this bit to connect an internal 1500 Ohm resistor between the
DPLUS line and V
CC
.
Clear:
The CPU clears this bit to disconnect an internal 1500 Ohm resistor between the
DPLUS line and V
CC
.
POR:
CONNECT=0
Chip Reset:
No change
Bus Reset:
No change
Pwr Down:
Read-write
Programming Notes:
The operation of the CONNECT bit depends on the setting of the VBGATE bit (page 76). If
CONNECT=1 and VBGATE=1, internal logic will not connect the pullup resistor unless V
BUS
is
detected to be valid on the V
BUS
pin. If VBGATE=0 the DPLUS pullup resistor is
unconditionally connected when CONNECT=1.
Only a power-on reset clears the CONNECT bit. If, during operation, an external reset is applied
to the MAX3420E via the INT pin, the CONNECT bit retains its state. This means that if a
device is connected to USB (CONNECT=1) when the RES# is asserted, it remains connected
throughout the reset and after the reset is removed (RES#=1).
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