KSZ8895 INFINEON [Infineon Technologies AG], KSZ8895 Datasheet - Page 96

• Manufacturer Part Number: KSZ8895
• Description: Integrated 5-Port 10/100 Managed Ethernet Switch with MII/RMII interface
• Manufacturer: INFINEON [Infineon Technologies AG]

Micrel, Inc.
The KSZ8895MQ/RQ/FMQ provides a total of 34 MIB counter per port. These counter are used to monitor the port
detail activity for network management and maintenance. These MIB counters are read using indirect memory
access as follows examples.
Programming Examples:
Note:
To read out all the counters, the best performance over the SPI bus is (160+3) × 8 × 80 = 104us, where there are 160 registers, 3 overhead, 8
clocks per access, at 12.5MHz. 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.
January 2011
(1) MIB counter read (read port 1 Rx64Octets counter)
(2) MIB counter read (read port 2 Rx64Octets counter)
(3) MIB counter read (read port 1 tx drop packets)
Write to Register 110 with 0x1c (read MIB counters selected)
Write to Register 111 with 0xe (trigger the read operation)
Then
Read Register 117 (counter value 31-24)
// If bit 31 = 1, there was a counter overflow
// If bit 30 = 0, restart (reread) from this register
Read Register 118 (counter value 23-16)
Read Register 119 (counter value 15-8)
Read Register 120 (counter value 7-0)
Write to Register 110 with 0x1c (read MIB counter selected)
Write to Register 111 with 0x2e (trigger the read operation)
Then
Read Register 117 (counter value 31-24)
//If bit 31 = 1, there was a counter overflow
//If bit 30 = 0, restart (reread) from this register
Read Register 118 (counter value 23-16)
Read Register 119 (counter value 15-8)
Read Register 120 (counter value 7-0)
Write to Register 110 with 0x1d
Write to Register 111 with 0x00
Then
Read Register 119 (counter value 15-8)
Read Register 120 (counter value 7-0)
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KSZ8895MQ/RQ/FMQ
M9999-012011-1.2