KSZ8995M A4 Micrel Inc, KSZ8995M A4 Datasheet - Page 59

• Manufacturer Part Number: KSZ8995M A4
• Manufacturer: Micrel Inc

Specifications of KSZ8995M A4

• Number Of Primary Switch Ports: 5
• Internal Memory Buffer Size: 64
• Operating Supply Voltage (typ): 1.8/2.5/3.3V
• Fiber Support: Yes
• Integrated Led Drivers: Yes
• Phy/transceiver Interface: MII/SNI
• Power Supply Type: Analog/Digital
• Package Type: PQFP
• Data Rate (typ): 10/100Mbps
• Vlan Support: Yes
• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Pin Count: 128
• Mounting: Surface Mount
• Jtag Support: No
• Operating Supply Voltage (max): 1.9/2.6/3.6V
• Operating Supply Voltage (min): 1.7/2.4/3V
• Operating Temperature Classification: Commercial
• Data Rate: 100Mbps
• Lead Free Status / RoHS Status: Compliant

(2) MIB counter read (read port 2 rx 64 counter)
(3) MIB counter read (read port 1 tx drop packets)
Note:
To read out all the counters, the best performance over the SPI bus is (160+3) × 8 × 200 = 260ms, where there are 160 register, 3 overhead, 8 clocks
per access, at 5MHz. 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. The per port MIB counters are designed as “read clear.” A per port MIB counter will be cleared after it is accessed. All port
dropped packet MIB counters are not cleared after they are accessed. The application needs to keep track of overflow and valid conditions on these
counters.
June 2009
KS8995M
Write to reg110 with 0x1c
(read MIB counter selected)
Write to reg111 with 0x2e
(trigger the read operation )
Then
Read reg117 (counter value 31-24)
// If bit 31 = 1, there was a counter overflow.
// If bit 30 = 0, restart (reread) from this register.
Read reg118 (counter value 23-16)
Read reg119 (counter value 15-8)
Read reg120 (counter value 7-0)
Write to reg 110 with 0x1d
Write to reg 111 with 0x00
Then
Read reg119 (counter value 15-8)
Read reg120 (counter value 7-0)
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M9999-062309
Micrel, Inc.