Inverse Multiplexing for ATM (IMA)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 33-39
33.4.4.2.2 IMA Group Receive State (IGRSTATE) The fields of the IGRSTATE register are shown in Figure33-18.Table33-12 describes the IGRSTATE bit fields.33.4.4.2.3 IMA Receive Group Frame Size The fields of the IRGFS register are shown in Figure33-19.

Table33-11. IGRCNTL Field Descriptions

Bits Name Description
0 GOTP Group order table pointer. Defines which group order table pointer (RGRPORDER0 or
RGRPORDER1) will be used for the cell extraction round-robin. Initialize to zero at group
startup.
1–2 Reserved, initialize to zero.
3-4 RXSC Receive status/control. Sets the receive mode of the IMA group.
00Filler mode. The IMA group processes only ICP cells. Data cells are replaced with filler
cells.
01Active mode. The IMA group is capable of receiving data cells.
1XReserved. D efaults to Filler Mode.
5 IDCR IDCR recovery enable. Selects the mode of the receive process activation function.
0 On-demand cell processing
1 IDCR-regulated cell processing
6-7 Reserved, initialize to zero.
0123 7
Field IDCR_DN GDSS

Figure 33-18. IMA Group Receive State (IGRSTATE)

Table33-12. IGRSTATE Field Descriptions

Bits Name Description
0 IDCR_DN IDCR Done. Microcode-managed parameter. When this bit is set by the microcode, the TRLR
value is valid and can be used to program the IDCR timer entry values for this group. Initialize
to zero at group startup.
1-2 GDSS Group delay synchronization state. Initialize to zero at group startup. Must be changed by
software to 01 after sufficient links have achieved frame synchronization. Subsequently
managed by microcode.
00Group delay synchronization process inhibited.
01Group delay synchronization process enabled.
10Group delay synchronization process in progress.
11Group delay synchronized.
Refer to Section33.5.4.10, “Receive Event Response Procedures.”
3-7 R eserved, initialize to zero.