DS3161 datasheet(82/384 Pages) MAXIM

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DS3161/DS3162/DS3163/DS3164

Figure 8-36 shows a multi-device transmit interface in packet transfer mode multiple packet transfer to different

PHY ports. On clock edge 2, the POS device polls PHY port 'N'. On clock edge 3, PHY port 'N' indicates to the

POS device that it can accept a block of packet data by asserting TPXA. On clock edge 4, the POS device selects

PHY port 'N'. On clock edge 5, the POS device starts a packet transfer to PHY port 'N' by asserting

TEN, placing

the first byte of packet data on TDATA, and asserting TSOX to indicate the transfer of the first byte of the packet.

On clock edge 6, the POS device de-asserts TSOX as it continues to place additional bytes of the packet on

TDATA. And, PHY port 'N' drives its TSPA output high. On clock edge 10, the POS device polls PHY port 'M'. On

clock edge 11, the POS device asserts TEOP to indicate the transfer of the last byte of the packet to PHY port 'N'

and PHY port 'M' indicates to the POS device that it can accept a block of packet data by asserting TPXA. On clock

edge 12, the POS device de-asserts

TEN to end the packet transfer process to PHY port 'N' and selects PHY port

'M'. On clock edge 13, the POS device starts a packet transfer to PHY port 'M' by asserting

TEN, placing the first

byte of packet data on TDATA, and asserting TSOX to indicate the transfer of the first byte of the packet. And, PHY

port 'N' tri-states its TSPA output. On clock edge 14, the POS device de-asserts TSOX as it continues to place

additional bytes of the packet on TDATA. And, PHY port 'M' drives its TSPA output high.

Figure 8-36. POS-PHY Level 2 Transmit Multiple Packet Transfer to Different PHY Ports

(Polled Status Mode)

TCLK

TADR

TPXA

…

TEN

TSOX

TEOP

TERR

TDAT

Transfer

To PHY

…

P62

P63 P64

TSPA

DS3161 Datasheet(PDF) 82 Page - Maxim Integrated Products