KSZ8873MLL/FLL/RLL Evaluation Board User’s Guide
Micrel, Inc.
January 11, 2011
Confidential
Rev. 1.1
5/10
MII connector for the Switch MII interface. It is to facilitate connection from the switch to either
the external CPU or the external PHY.
Figure 1: KSZ8873MLL/FLL/RLL Evaluation Board Block Diagram
The KSZ8873MLL/FLL/RLL evaluation board is easy to use. There are programmable LED
indicators for link and activity on the PHY ports and a power LED. A manual reset button allows
the user to reset the board without removing the power plug. The 5V power on the board can be
supplied by a standard 5VDC power supply (close pin 1-2 of JP400 jumper) or by the USB cable
(close pin 2-3 of JP400 jumper) which is used to access the registers in SPI mode. A standard
5VDC power supply is included so that the user can supply power from any 110 Volt AC wall or
bench socket. Before to start to use the evaluation board, make sure the power connectors
JP403, JP404, JP405 and JP31 are connected, and close pin 1-2 of J14.
4.1 Strap In Mode
Strap in configuration mode is the quickest and easiest way to get started. In this mode, the
KSZ8873MLL/FLL/RLL acts as a standalone 3-port switch. Simply set the board’s configuration
jumpers to the desired settings and apply power to the board. The configuration can be changed
while power is applied to the board by changing the jumper settings and pressing the convenient
manual reset button for the new settings to take effect. Note that even if no external strap in
values are set, internal pull up and pull down resistors will set the KSZ8873MLL/FLL/RLL default
configuration. Section 4.1.1 covers each jumper on the board and describes its function. To
start in strap in configuration mode, make sure that the USB cable is unplugged, JP34, JP35, JP3
and JP9 are connected, JP21, JP25 have jumpers fitted between pins 2 to 3.