Altera POS-PHY Level 2 and 3 Compiler - Manual (Page 55)

Chapter 3: Functional Description 3–27
Interface Signals
© November 2009 Altera Corporation POS-PHY Level 2 and 3 Compiler User Guide
Preliminary
■ Master sink to slave source
The data flow on the Atlantic interface can be in either direction.
A slave sink responds to write commands from the master source and behaves like a
synchronous FIFO buffer.
A master sink generates read commands to a slave source, when it requires data, and
behaves like a synchronous FIFO buffer controller.
Table 3–13 shows the Atlantic data interface signal definitions.
Figure 3–17. Atlantic Interface Control Options
Note to Figure 3–17 :
(1) Buses are unidirectional only.
Atlantic
Interface
Master
Source
Atlantic
Interface
Slave
Sink
mty
err
eop
sop
par
dat
ena
dav
mty
err
eop
sop
par
dat
ena
val
dav
Atlantic
Interface
Master
Sink
Atlantic
Interface
Slave
Source
Table 3–13. Atlantic Interface Data Signals (Part 1 of 2)
Signal Description
dat[63:0]
dat[31:0]
dat[15:0]
dat[7:0]
Data bus. dat carries the packet octets that are transferred across the interface. Data is transmitted in
big-endian order on dat, that is, most significant bit (MSB) first and all valid bits are contiguous with
the MSB.
par Parity signal (optional). par indicates the parity calculated over the dat bus. Odd and even parity are
supported.
sop Start of packet. sop delineates the packet boundaries on the dat bus. When sop is high, the start of
the packet is present on the dat bus. sop is asserted on the first transfer of every packet.
eop End of packet. eop delineates the packet boundaries on the dat bus. When eop is high, the end of the
packet is present on the dat bus. mty indicates the number of invalid bytes the last word is composed
of when eop is asserted. eop is asserted on the last transfer of every packet.