28478G-18 Mindspeed Technologies, 28478G-18 Datasheet - Page 124

• Manufacturer Part Number: 28478G-18
• Description: Multichannel Synchronous Communications Controller 208-Pin BGA
• Manufacturer: Mindspeed Technologies

Specifications of 28478G-18

• Package: 208BGA
• Maximum Data Rate: 32768 Kbps
• Transmission Media Type: Wire
• Power Supply Type: Analog
• Typical Supply Current: 250 mA
• Typical Operating Supply Voltage: 3.3 V
• Minimum Operating Supply Voltage: 3 V
• Maximum Operating Supply Voltage: 3.6 V

6.1
There are five levels of reset state:
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There are two ways to assert a reset:
1. Assert the PCI reset signal pin, PRST*.
2. Assert a service request through the host interface to perform the soft chip reset, soft group reset, channel
6.1.1
The PCI reset is the most thorough level of reset in MUSYCC. All subsystems enter into their initial states. PCI
reset is accomplished by asserting the PCI signal, PRST*.
The PRST* signal is an asynchronous signal on the PCI bus. The reset signal can be activated in several ways.
The system must always assert the reset signal on power-up. Also, a host bus to a PCI bus bridging device should
provide a way for software to assert the reset signal. Additionally, software-controlled circuitry can be included in
the system design to specifically assert the reset signal on demand.
Asserting PRST* towards MUSYCC guarantees that data transfer operations and PCI device operations will not
begin until MUSYCC has been properly initialized for operation. Upon entering the PCI reset state, MUSYCC
outputs a three-stated signal on all output pins and stops activity on all subsystems including the host interface,
serial interface, and expansion bus.
A PCI reset signal in MUSYCC takes one PCI clock cycle to complete, after which the host can communicate with
MUSYCC using the PCI configuration cycles.
6.1.2
A Soft Chip Reset (SCR) is a device-wide reset without the host interface’s PCI state being reset. Serial interface
operations and EBUS operations are stopped. The soft chip reset state is entered in one of two ways:
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28478-DSH-002-E
Hard PCI Reset
Soft Chip Reset
Soft Group Reset
Channel Activation
Channel Deactivation
activation, or channel deactivation.
as a result of the PCI reset
as a result of a soft chip reset service request
Reset
Hard PCI Reset
Soft Chip Reset
Preliminary Information / Mindspeed Proprietary and Confidential
6.0 Basic Operation
Mindspeed Technologies
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