XC68HC08KH12 Motorola, XC68HC08KH12 Datasheet - Page 121

• Manufacturer Part Number: XC68HC08KH12
• Description: MICROCONTROLLER
• Manufacturer: Motorola

9.4.2 USB HUB Downstream Port Control Register (HDP1CR-HDP4CR)
MC68HC(7)08KH12
MOTOROLA
—
Rev. 1.0
Address: $0051
Address: $0054
D0+/D0– — Root Port Differential Data
PEN1-PEN4 — Downstream Port Enable Control Bit
Reset:
Reset:
Read:
Read:
Write:
Write:
EOF2 is generated by KH12 every millisecond, if SOF is not detected
when three or more EOF2 has occurred, software can set the
SUSPND-bit and put KH12 into suspend mode.
These read only bits are the differential data shown on the HUB root
ports. When the bit SUSPND is 0, the data is the latched state at the
last EOF2 sample point. When the bit SUSPND is 1, the data reflects
the current state on the data line while accessing this register.
This read/write bit determines whether the enabled or disabled state
should be assigned to the downstream port. Setting this bit 1 to
enable the port and clear the bit to disable the port. In the enabled
state a full-speed port propagates all downstream signaling, a low-
speed port propagates downstream low-speed packet traffic when
preceded by the preamble PID. An enabled port propagates all
upstream signaling including full speed and low speed packets. This
Figure 9-3. USB HUB Downstream Port Control Registers
PEN1
PEN4
Bit 7
Universal Serial Bus Module (USB)
0
0
LOWSP1
LOWSP4
= Unimplemented
6
0
0
(HDP1CR-HDP4CR)
RST1
RST4
5
0
0
RESUM1
RESUM4
4
0
0
I/O Register Description of the HUB function
X = Indeterminate
SUSP1
SUSP4
Universal Serial Bus Module (USB)
3
0
0
2
0
0
0
0
Advance Information
D1+
D4+
1
X
X
Bit 0
D1–
D4–
X
X
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