AM335x Dual Gigabit Ethernet

Charles H

I have seen some confusing comments in regards to the AM335x devices with the Dual Gigabit Ethernet.. Is there in deed 2 separate RGMII MAC interfaces to the outside world? Can both Ethernet ports run at 1Gbps rate? Customer wants to use as a routing device..What limitations are there in running Gigabit Ethernet in one port and switching out thru the other port? I thought a previous post suggested that only 1 port could be 1Gbps and the other would be 100Mbps? Is that correct?

over 11 years ago

0 Biser Gatchev-XID over 11 years ago

TI__Guru**** 393215 points

Hi Charles,

Yes, there are 2 RGMII MAC interfaces in the AM335X ZCZ package. If you take a look at the Starter Kit, it has them both routed out with GHz PHYs (http://www.ti.com/tool/tmdssk3358 with links to wiki pages). The limitations come from the processor data handling capability. See this thread (http://e2e.ti.com/support/arm/sitara_arm/f/791/t/200496.aspx second post) for more details. The CPSW subsystem is described in detail in the AM335X TRM, Rev. I, section 14. Don't forget to check the AM335X Errata, Rev. F too, there are several advisories concerning the CPSW there.

0 Charles H over 11 years ago in reply to Biser Gatchev-XID

Intellectual 895 points

Biser,

Thank you..Can the part be used as a router with the Giga E ports being on separate distinct Networks?

I guess there is confusion since the ports go back to a switch. Will they remain isolated from each other? So you could filter only info meant to go to from 1 port to the other and vice versa?

Charles

0 Biser Gatchev-XID over 11 years ago in reply to Charles H

TI__Guru**** 393215 points

Yes this is possible. The AM335X Technical Reference Manual, Rev. I, section 14.3.2.7.2 describes the packet forwarding processes.

Processors

Processors forum

AM335x Dual Gigabit Ethernet