cx28224 Mindspeed Technologies, cx28224 Datasheet - Page 79

• Manufacturer Part Number: cx28224
• Description: Cx28224/5/9 Inverse Multiplexing For The Atm Ima Family
• Manufacturer: Mindspeed Technologies

CX28224/5/9 Data Sheet
4.3
4.4
28229-DSH-001-D
IMA UTOPIA
TC Block UTOPIA
This is the normal interface for IMA applications and is selected as shown in
Table
It is intended to interface to a single ATM Layer device and appear as a multi-port
PHY device.
The number of “ports” or channels on the IMA Subsystem is the sum of the number of
configured IMA groups plus the number of pass-through facilities. The IMA
CX28229 requires a unique Utopia address for each channel (IMA group or pass-
through). There are no restrictions placed on the address assignment and not all 32
locations are normally used.
If only one channel is programmed, (a single IMA group and no pass-through
facilities), then the CX28229 can be compatible with UTOPIA Level 1 by fixing the
address lines to a specific value and setting the IMA group’s ATM address (through
the software driver) to that value.
The CX28229 provides numerous options to match non-standard UTOPIA
controllers. See the IMA_ATM_UTOPIA_BUS_CTL register, 0x413, for more
information.
This interface is selected when using the device as a stand-alone cell delineator. See
Table 4-1
2 interface with the following enhancements.
UDF2 Programmability
The user can program the contents of the UDF2 byte when operating in 16-bit
UTOPIA mode. Be default, the contents of the UDF2 byte (detailed in Table 10-9) on
the receive interface will match the default value of the UTOPIA port address. This
can be changed by writing the desired value to the corresponding UDF2 control
register, 0x0F. Bus width is controlled by bit 5 of the ATMINTFC register.
Port Number Assignment
The UTOPIA address for each port is stored in bits 0–4 of the UTOP2 register (0x0E).
The default for this value is the port number. For example, the UTOP2 register for
port 4 (0x10E [with the offset]) defaults to 04 hex. However, the value can be
changed to any value from 00–1E hex by programming the register to accommodate
multiple devices on the same UTOPIA bus. The value 1F hex is reserved for the null
address. The UTOPIA address should be changed only when the device or port is in
the reset state.
NOTE:
4-1.
and
0x1F can be assigned as a valid port address to enable 32 port bypass.
Figure 4-1
Mindspeed Technologies
Section
2.4. It interfaces to the ATM layer as a normal UTOPIA Level
illustrates the connections to/from the ATM Layer device.
™
UTOPIA Interfaces
4
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3