8101 Datasheet, PDF (76/172 Pages) LSI Computer Systems – Gigabit Ethernet Controller

2.19.3 Counter Rollover
Counters normally roll over to zero when they exceed their maximum
count, (receive an increment when counter is at maximum count). The
counters can be programmed to freeze and stop counting once they
reach their maximum count. Setting the CTR_ROLL bit in “Register 9–
Configuration 3‚" Section 4.3.10, programs the counters to freeze when
they reach their maximum count.
2.19.4 Counter Maximum Packet Size
The maximum packet size used for the management counter statistics
can be programmed to be one of four values. Setting the CMXPKT[1:0]
bits in “Register 10–Configuration 4‚" Section 4.3.11, select the maximum
packet size. This selection is described in the register descriptions for
those registers and is also summarized in Table 2.15.
The bits in Table 2.15 affect the maximum packet size for the counters
only; the maximum packet size for the MAC section is described in
Section 2.8, “Receive MAC”.
Table 2.15 Counter Maximum Packet Size Selection
CMXPKT [1:0]
11
10
01
00
Maximum Packet Size (bytes)
Unlimited
1535
1522
1518
2.19.5 Counter Reset
Setting the CTRRST bit in “Register 7–Configuration 1‚" Section 4.3.8,
resets all counters to zero. Asserting the controller reset pin, RESETn,
also resets the counters to zero.
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Functional Description
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