Achronix Speedster22i SerDes - Manual (Page 40)

PMA Test Pattern Generator
The PMA supports a built in transmit data pattern generator that can be used for transmit
characterization. The test pattern generator can transmit PRBS patterns and user defined
patterns. The PRBS patterns supported are shown in “Table 6: PRBS Patterns in PMA” below:
Table 6: PRBS Patterns in PMA
Bus Width PRBS Pattern Available
PRBS-7 1+x 6 +x 7
PRBS-23 1+x 18 +x 23
PRBS-31 1+x 28 +x 31
The transmit pattern generator can generate user defined pattern by configuring control
registers. The user defined pattern can be a 40 bit memory pattern.
PMA Test Pattern Checker
The PMA Test pattern checker on the receive data path can be used to check all the standard
data patterns and user defined patterns by enabling the self test checker. The standard data
patterns include the PRBS patterns as described in Table above. The user defined pattern is a
40-bit memory pattern checker. The PRBS transmitter and receiver are enabled by selecting
the loopback modes described in section “Dynamic Read/Write of SerDes Registers (Through
SBUS)”.
PCS Test Pattern Generator
The PCS can be programmed to transmit test pattern data instead of user provided transmit
data coming from fabric interface. The test pattern generator is used to check the quality of
the serial link and supports various standard patterns. The test pattern generator can
transmit PRBS patterns and user defined patterns. The PRBS patterns currently supported are
shown in “Table 7: PRBS Patterns in the PCS”.
PRBS Generator
Various PRBS patterns can be generated by the transmit block which are summarized in
“Table 7: PRBS Patterns in the PCS”.
Table 7: PRBS Patterns in the PCS
Bus Width PRBS Pattern Available
PRBS-7 1+x 6 +x 7
PRBS-15 1+x 14 +x 15 .
PRBS-20 1+x 3 +x 20
PRBS-23 1+x 18 +x 23
PRBS-31 1+x 28 +x 31
40 UG028, July 1, 2014