Philips Integrated Circuits PDIUSBH12 - Manual (Page 16)

Philips Semiconductors Product specification
PDIUSBH12 USB 2-port hub
1999 Jul 22 16
Get Port Status
Command : E0h–E1h
Data : Read 1 or 2 bytes
The Get Port Status Command can be followed by one or two data
reads. The first byte returned contains the port status. The second
byte returned is the port status change byte.
Port Status Byte
SV00846
POWER ON VALUE
CONNECT
ENABLED
SUSPEND
OVERCURRENT
RESET
POWER
LOW SPEED
7 6 5 4 3 2
0
1
0
0
0 0 0 0 X 0
RESERVED
Connect A ‘1’ indicates that a device is connected on
this port of the hub.
Enabled A ‘1’ indicates that this port is enabled.
Suspend A ‘1’ indicates that this port is suspended.
OverCurrent A ‘1’ indicates that overcurrent condition
exists on this port. In mode 0 of operation,
this bit is the same for all ports. In mode 1,
individual port overcurrent indication is
possible.
Reset A ‘1’ indicates that bus reset on this port is in
progress. When reset is completed (nominal
duration of 10 ms), this bit indicates a ‘0’.
Power A ‘1’ indicates that power is supplied to
downstream ports. Since the PDIUSBH12
supports gang mode power switching, this
bit is the same for all ports.
Low Speed A ‘1’ indicates that low speed device is
connected to this port. This bit is only valid
when Connect bit is a ‘1’.
Port Status Change Byte
The description for the Port Status Change Byte is similar to the Port
Status Byte except that the value of the bits are ‘1’ only when a
change has occurred.
SV00847
POWER ON VALUE
CONNECT
ENABLED
SUSPEND
OVERCURRENT
RESET
7 6 5 4 3 2
0
1
0
0
0 0 X 0 X X
RESERVED
Set Status Change Bits
Command : F7h
Data : Write 1 byte
For assembling the hub’s status change register, the device needs
some additional information from the controller, i.e. the Local Power
Status Change bit and the embedded function Status Change bit.
These are provided by the Set Status Change Bits command. This
command is always followed by one data write which contains the
Local Power Status Change bit at the LSB and the embedded
function Status Change bit at position 1. All other bits should be 0.
SV00848
7 6 5 4 3 2
0
1
0
0
POWER ON VALUE
LOCAL POWER
EMBEDDED FUNCTION 1
0 0 X X X X
RESERVED
EMBEDDED FUNCTION 6
EMBEDDED FUNCTION 7