VSC8502 Reference Board
VPPD-03822 VSC8502 User Guide Revision 1.0
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vsc8502_RGMII_2nsGTXCLKdelay.txt: configure the MAC interface to RGMII mode with 2.0ns
GTX_CLK delay compensation.
vsc8502_10BTe_Config.txt: optimize the copper media interface settings for 10BASE-Te.
To load and execute configuration scripts, click “Device” on the top menu and choose “Load Config
Script” option then select the desired script file. Once the script is executed, it should say “LOADED n
REGISTERS” at the bottom left corner of the GUI Window, where n is the loaded registers count.
4.3.2
Copper Media Operation (Auto-negotiation Enabled)
The easiest configuration for passing traffic is with Autoneg enabled (MII 0.12 = 1). Use MII Register 0, 4
and 9 to change speed and restart autoneg (MII 0 bit 9) to advertise new settings. As per the datasheet
descriptions, the commonly-used speed advertisement definitions are as follows:
Table 2 • Auto-Negotiation Advertisements
MII reg 4
bits 8:7
MII reg 4
bits 6:5
MII reg 9
bits 12:11
MII reg 9
bits 9:8
1000BT Master mode
N/A
N/A
11
11
1000BT Slave mode
N/A
N/A
10
11
100 BASE-TX Full Duplex
11
N/A
N/A
00
10 BASE-T Full Duplex
00
11
N/A
00
The following steps are used to configure a link:
Set up the Copper traffic source (i.e., IXIA or Smartbits)
Run the vsc8502_init.txt script
Connect Ethernet cable(s) to a single or multiple RJ-45 ports
Connect 0.1 inch shunt jumpers between row-2 and row-3 of RGMII
connectors as external loopback within a single port
Configure MAC interface for RGMII mode, enable RX_CLK output and set
RX_CLK or GTX_CLK delay, as described in Configuration section of the
datasheet. Alternatively, this can also be done by running either one of the
two RGMII configuration scripts.
Configure auto-negotiation as per above and re-start ANEG (MII bit 0.12)
The linkup bit is in MII Reg 1, bit 2 (MII 1.2), read it twice to update
Traffic should now be flowing.
