MC141555 View Datasheet(PDF) - Motorola => Freescale
Part Name
Description
Manufacturer
MC141555 Datasheet PDF : 16 Pages
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Freescale Semiconductor, Inc.
SYSTEM DESCRIPTION
MC141555 is booted up from the Power-On Reset which
will initialize all the internal hardware circuitry and reset the
program counter of the internal processor. During Power-On
Reset, MC141555 must be set to the desired configuration
by the input states of the pins, OVR5/GANG, PWRSW5,
DP5/SEL1 and DM5/SEL0. See Table1 Configuration
Selection for detail.
After Power-On, the Hub Repeater will handle the con-
nectivity in per packet basis, and all downstream ports tran-
sition to the powered off state. After all initialization, the Hub
Controller takes over the responsibility for receiving Host’s
commands, Downstream Power Management and to report
status in per port basis while Repeater is detecting the con-
nectivity of each downstream port.
MC141555 accepts the Host Reset request to generate a
per port reset and receives reset signalling from root port to
complete its own reset sequence.
Table 1. Configuration Selection
DP5/ DM5/ PWRSW5 OVR5/
SEL1 SEL0
GANG
Configuration
0
0 PWRSW5 OVR5 Self Power & Individu-
al Control
0
1
X
1 Bus Power & Individu-
al Control
0
1
X
0 Bus Power & Ganged
Control
X: don’t care
HUB CONFIGURATION
MC141555 can be configured as one of the three operating
modes: Self Power Mode with Individual Control, Bus Power
Mode with Individual Control and Bus Power Mode with
Ganged Control.
(a) Self-powered Mode with Individual Control
(Monitor Application)
During Power-On Reset, pull DP5/SEL1 and DM5/SEL0
low to select this mode. Meanwhile, MC141555 is configured
to be self powered with 5 downstream ports whose power
management is in Individual Control; that is, after Power-On
Reset, DP5/SEL1 acts as DP5, DM5/SEL0 acts as DM 5 and
OVR5/GANG acts as OVR5 .
(b) Bus-powered Mode with Individual Control
During Power-On Reset, pull DP5/SEL1 low, pull OVR5/
GANG and DM5/SEL0 high to select this mode. Meanwhile,
MC141555 is configured to be bus powered with 4 down-
stream ports whose power management is in Individual Con-
trol; that is, after Power-On Reset, DP5/SEL1, DM5/SEL0,
OVR5/GANG and PWRSW5 have no further usage.
(c) Bus-powered Mode with Ganged Control
During Power-On Reset, pull DP5/SEL1 and OVR5/
GANG low and pull DM5/SEL0 high to select this mode.
Meanwhile, MC141555 is configured to be bus-powered with
4 downstream ports whose power management is in
Ganged Control. In this mode, only PWRSW1 and OVR1 are
dedicated to power management for all 4 downstream ports.
All three operating modes with pin input states during
Power-On Reset are summarized in Table 1.
MOTOROLA
For More Information On This Product,
Go to: www.freescale.com
MC141555
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