Cypress CYS25G0101DX-ATC Manual De Usuario
CYS25G0101DX-ATC Evaluation Board User’s Guide
13
5.2 Line Loopback
In the Line Loopback mode, serial data (from IN±) will loop through the serial input buffer and CDR block to the serial output buffer
(OUT±).
(OUT±).
Figure 5
shows the data path (bold line) of the Line Loopback mode. To select the Line Loopback mode:
1. SW1-3 (LINELOOP) must be in ON position
2. All other dip switch settings must be in their default positions as stated in
Table 4
3. TEST0, jumper J6 must be opened
4. Apply the Testing Hookup illustrated in
Figure 8
to
Figure 10
Figure 5. Line Loopback Mode Data Path
TXD
15:0
15:0
TX PLL
x16
/16
RXD
15:0
SHIFTER
RX CDR
PLL
Input
Register
Output
Register
FIFO
(5byte)
SHIFTER
/16
RXCLKOUT
REFCLK
TXCLK
TXCLKIN
DIAGLOOP
(SW1-2) = OFF
(SW1-2) = OFF
LINELOOP
SW1-3 = ON
SW1-3 = ON
LOOPA
SW1-4 = OFF
SW1-4 = OFF
IN
±
OUT
±