
PRELIMINARY
INVERSE MULTIPLEXING OVER ATM
PM7341 S/UNI-IMA-84
DATASHEET
PMC-2000223
ISSUE 4
INVERSE MULTIPLEXING OVER ATM
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
333
Transmit IMA Group Configuration Table (MEM_SELECT=0)
Purpose: Contains IMA configuration data programmed by PM.
Usage: IMA Groups only.
Maintained by: Microprocessor.
Record Size: One 32-bit word.
MEM_ADDR = 0x2A0 + Group Tag
Table 32 Transmit IMA Group Configuration Table Record
Bits
Parameter
Description
31:23
Unused
22:16
VPHY
Address
VPHY address (group FIFO number) which is
assigned to this group. This field should be modified
by PM only during group configuration. Valid values
are 0 to 83.
15:9
Unused
10
Disable Cell
Discard
Configuration bit which determines if the ATM cell
discarding feature is enabled for this IMA Group.
When set to 0, ATM cells will be read and discarded
from the group FIFO (one for each request) if there
are no active links in the group. When set to 1, cell
discarding will not occur for the group.
9
Stuff
Advertise
Mode
Configuration bit which determines whether stuff cell
advertising is done either four ICP cells ahead or one
ICP cell ahead of the stuff event. This bit should be
changed only on Group startup, otherwise the number
of cells between TRL stuff events will not be correct.
0 = one ICP cell ahead; 1 = four ICP cells ahead
8
Stuff Mode
Configuration bit which determines whether ITC or
CTC stuff mode is actually used for this group. Note it
is possible to advertise ITC Transmit Clock Mode in an