DS3161/DS3162/DS3163/DS3164
Figure 8-35 shows a multi-device receive interface in byte transfer mode multiple packet transfer from different
PHY ports/devices. Prior to clock edge 1, a packet data transfer was initiated from PHY port '1', and PHY ports '2',
'3', and '4' indicated to the POS device that they have a block of packet data or an end of packet ready for transfer
by asserting their RDXA. On clock edge 2, the POS device indicates to PHY port '1' that it cannot accept any more
data transfers by removing its address from RADR, and indicates to PHY port '2' that it is ready to accept a block of
packet data by placing its address on RADR and leaving
REN asserted. On clock edge 3, PHY port '1' stops
transferring packet data, and PHY port '2' starts a packet transfer by leaving RVAL asserted, placing the first byte
of the packet on RDATA, and asserting RSOX to indicate that this is the first transfer of the packet. On clock edge
4, PHY port '2' de-asserts RSOX as it leaves RVAL asserted and continues to place additional bytes of the packet
on RDATA. On clock edge 8, the POS device de-asserts
REN to indicate to PHY port '2' that it cannot accept any
more data transfers. On clock edge 9, PHY port '2' ends the packet transfer process by de-asserting RVAL and tri-
stating its RVAL, RDATA, RSOX, REOP, and RERR outputs. And, the POS device indicates to PHY port '3' that it
is ready to accept a block of packet data by placing its address on RADR and reasserting
REN. On clock edge 10,
PHY port '3' continues a packet transfer by asserting RVAL and placing the next byte of packet data on RDATA.
On clock edge 14, PHY port '3' places the last byte of the packet on RDATA, and asserts REOP to indicate that this
is the last transfer of the packet. On clock edge 15, PHY port '3' de-asserts RVAL and REOP ending the packet
transfer process, as well as, de-asserting RDXA to indicate that it does not have another block of packet data or an
end of packet ready for transfer. On clock edge 16, the POS device indicates to PHY port '4' that it is ready to
accept a block of packet data by placing its address on RADR and leaving
REN asserted. On clock edge 17, PHY
port '4' starts a packet transfer by leaving RVAL asserted, placing the first byte of the packet on RDATA, and
asserting RSOX to indicate that this is the first transfer of the packet. On clock edge 18, PHY port '4' de-asserts
RSOX as it leaves RVAL asserted and continues to place additional bytes of the packet on RDATA.
Figure 8-35. POS-PHY Level 2 Receive Multiple Packet Transfer from Different PHY
Ports/Devices (Direct Status Mode)
RCLK
RDXA[1]
RADR
RDXA[2]
RDXA[3]
RDXA[4]
1
19
20
23
4
5
7
6
8
10
11
12
13
14
15
16
17
18
9
RSOX
REOP
RERR
RDATA
Transfer
From PHY
RVAL
REN
P34
P1
P2
P41
…
P42
P35
'4'
1F
'3'
'1'
'2'
…
P19
P20
P2
P63
X
P64
P3
'1'
'2'
'3'
'4'
P4
P43
P1