Inverse Multiplexing for ATM (IMA)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 33-33
33.4.4.1.4 ICP Cell Templates
The ICP cell templates are areas of memory provided by software to the microcode f or construction of ICP
cells for transmission. Software prepares the fields which are common to the group (i.e. class B, C, D, and
E parameters). The other (class A) parameters will be written to the appropriate fields by the microcode.
The template is 53 bytes long and must be aligned on a 64-byte boundary.
Table33-9 describes the format of a group order table entry. The ICP cell template is formatted as
byte-swapped, and additionally the ICP cell header is bitswapped. [This is due to hardware
implementation, and does not imply the order of transmission of the cell. The transmission of the cell is
per the ATM standard.] Reflecting this byte-swap, the offset column gives the offset in DPRAM from the
ICP template base.
Table33-8. Transmit Group Order Table Entry Field Desc riptions
Bits Name Description
0–2 — Reserved
3–7 PHY
ADDRESS
PHY address (Up to 31 PHYs[0–30]) of the link transmitting in this position in the round-robin.
A value of 0x1F in this field indicates the end of the group order table.
Table 33-9. ICP Cell Template 1
Offset Name Width Description
0x00 ICP CELL HEADER Word ICP cell header. Program to 0xD0000000.
0x04 ICP Cell Offset Byte Microcode-managed area. Microcode will program this field
dynamically.
0x05 IMA Frame Sequence
Number
Byte Microcode-managed area. Microcode will program this field
dynamically.
0x06 Cell ID and Link ID Byte Microcode-managed area. Microcode will program this field
dynamically.
0x07 OAM LABEL Byte IMA Version value.
1 IMA Version 1.0
3 IMA Version 1.1