
Micrel, Inc.
KSZ8851SNL/SNLI
August 2009
70
M9999-083109-2.0
Offset
Counter Name
Description
0x1C
TxTotalCollision
Tx total collision, half duplex only
0x1D
TxExcessiveCollision
A count of frames for which Tx fails due to excessive collisions
0x1E
TxSingleCollision
Successfully Tx frames on a port for which Tx is inhibited by exactly one collision
0x1F
TxMultipleCollision
Successfully Tx frames on a port for which Tx is inhibited by more than one collision
Table 14. Port 1 MIB Counters Indirect Memory Offsets
Example:
1. MIB Counter Read (read port 1 “Rx64Octets” counter at indirect address offset 0x0E)
Write to reg. IACR (0xC8) with 0x1C0E (set indirect address and trigger a read MIB counters operation)
Then
Read reg. IADHR (MIB counter value 31-16)
Read reg. IADLR (MIB counter value 15-0)
Additional MIB Information
In the heaviest condition, the byte counter will overflow in 2 minutes. It is recommended that the software read all
the counters at least every 30 seconds.
MIB counters are designed as “read clear”. That is, these counters will be cleared after they are read.