Inverse Multiplexing for ATM (IMA)
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Freescale Semiconductor 33-45
0x07 DFC Byte Number of frames to discard on a this link until it is caught up with the
other links in this group (long propagation delay). Microcode-managed
parameter.
0x08 DCBSP Hword IMA link delay compensation buffer start pointer. This parameter forms
bits 12-27 of the pointer; bits 0-11 are from IMAEXTBASE, and bits
28-31 are zero. Refer to Section33.4.6.2, “Delay Compensation
Buffers (DCB) for more details.
0x0A DCBEP Hword IMA link delay compensation buffer end pointer. This parameter forms
bits 12-27 of the pointer; bits 0-11 are from IMAEXTBASE, and bits
28-31 are zero. Refer to Section33.4.6.2, “Delay Compensation
Buffers (DCB) for more details.
0x0C DCBFP Hword IMA link delay compensation buffer fill pointer. Microcode-managed
parameter. This parameter forms bits 12-27 of the pointer; bits 0-11 are
from IMAEXTBASE, and bits 28-31 are zero.
Initialize to DCBSP at link startup.
0x0E DCBRP Hword IMA link delay compensation buffer read pointer. Only used during
group delay synchronization and link addition. Microcode-managed
parameter. This parameter forms bits 12-27 of the pointer; bits 0-11 are
from IMAEXTBASE, and bits 28-31 are zero.
0x10 RICPCH Hword Receive ICP channel number. ATM receive channel number to which
received ICP cells are sent.
0x12 IRINTMSK Byte IMA receive interrupt mask. Has the same format as the IMA interrupt
queue entry.; however, only receive-related bits are relevant. Setting a
bit enables the associated interrupt; clearing a bit masks it.
For group-related events, only the mask register for the TRL is
referenced.
0x13 LICPOS Byte Link ICP offset. Program to the ICP offset validated for this link.
0x14 IRSEC Word IMA receive stuff event counter. Increments each time a stuff event is
received on this ink. Initialize to zero at link startup.
0x18 ANOMALY_CTR Byte Anomaly counter. Microcode-managed parameter. Initialize to zero at
link startup.
0x19 ALPHABETA_CTR Byte Alpha/beta counter. Microcode-managed parameter. Initialize to zero at
link startup.
0x1A GAMMA_CTR Byte Gamma counter. Microcode-managed parameter. Initialize to zero at
link startup.
0x1C DEFECT_CTR Word Defect counter. This counter is active while the link is in the
Loss-of-IMA-Frame (LIF) state and is used to ensure IFSD interrupts
are generated for every GAMMA+2 frames. Software can use the
period interrupt issued by this counter in order to determine if the link
is taking too long to synchronize. The DEFECT_CTR is active before
IFSM reaches SYNC. It starts counting from the first cell received and
will count from 0 to (GAMMA+2) x M. When it reaches (GAMMA+2) xM
an IFSD interrupt is generated and the counter is reset. Upon reception
of the next cell it starts to count again and subsequent interrupts are
generated. Microcode managed parameter. Initialize to zero at link
startup.
Table33 -19. IMA Link Receive Table Entry1 (continued)
Offset Name Width Description