KSZ9021RL-EVAL Board User’s Guide
Micrel, Inc.
March 20, 2009
Rev.
1.0
7/24
4.1 Jumper Setting & Definition
At power-up, the KSZ9021RL device is configured via strapping pins that are set by external pull-
up and pull-down resistors. The KSZ9021RL-EVAL board provides jumpers for the KSZ9021RL
device strap-in settings and for selective board options.
Jumpers allow for quick configuration and re-configuration. To override the current KSZ9021RL
device and board settings, simply select and close the desired jumper setting(s) and toggle the
on-board manual reset button (S1) for the new setting(s) to take effect.
The KSZ9021RL-EVAL board jumper settings are defined in the table below.
Jumper
KSZ9021RL Pin Name
Setting
Function
KSZ9021RL Device Strapping Pins
Close pins (1, 2)
Set MODE3 = 1
JP1 MODE3
Close pins (2, 3)
Set MODE3 = 0
Close pins (1, 2)
Set MODE2 = 1
JP2 MODE2
Close pins (2, 3)
Set MODE2 = 0
Close pins (1, 2)
Set MODE1 = 1
JP3 MODE1
Close pins (2, 3)
Set MODE1 = 0
Close pins (1, 2)
Set MODE0 = 1
JP4 MODE0
Close pins (2, 3)
Set MODE0 = 0
Close pins (1, 2)
Set PHYAD2 = 1
JP19 PHYAD2
Close pins (2, 3)
Set PHYAD2 = 0
Close pins (1, 2)
Set PHYAD1 = 1
JP9 PHYAD1
Close pins (2, 3)
Set PHYAD1 = 0
Close pins (1, 2)
Set PHYAD0 = 1
JP10 PHYAD0
Close pins (2, 3)
Set PHYAD0 = 0
Close pins (1, 2)
Enable 125 MHz Clock Output
JP16 CLK125_EN
Close pins (2, 3)
Disable 125 MHz Clock Output
Close pins (1, 2)
Select Single LED Mode
JP20 LED_MODE
Close pins (2, 3)
Select Tri-color Dual LED Mode
KSZ9021RL-EVAL Board Settings
Close pins (1, 2)
Use for Single LED Mode
JP26 LED2
Close pins (2, 3)
Use for Tri-color Dual LED Mode
Close pins (1, 2)
Use for Single LED Mode
JP27 LED1
Close pins (2, 3)
Use for Tri-color Dual LED Mode
Close pins (1, 2)
1
Select 2.5V for KSZ902RL digital I/Os
JP23 DVDDH
Close pins (2, 3)
Select 3.3V for KSZ9021RL digital I/Os
Close Jumper
Close MDC signal to USB Controller (U8)
JP21 MDC
Open Jumper
Open MDC signal to USB Controller (U8)
Close Jumper
Close MDIO signal to USB Controller (U8)
JP22 MDIO
Open Jumper
Open MDIO signal to USB Controller (U8)
Note:
1
If DVDDH is set to 2.5V, MDC/MDIO programming via USB Controller (U8) is disabled.
Table 1. KSZ9021RL-EVAL Board – Jumper Definition