Visible to Intel only — GUID: nik1398984227879
Ixiasoft
Visible to Intel only — GUID: nik1398984227879
Ixiasoft
14.5.3. RX PMA Parameters
Parameter |
Range |
Description |
---|---|---|
Enable CDR dynamic reconfiguration |
On/Off |
When you turn this option On, you can dynamically change the data rate of the CDR circuit. |
Number of CDR reference clocks |
1–5 |
Specifies the number of reference clocks for the CDRs. |
Selected CDR reference clock |
0–4 |
Specifies the index of the selected CDR reference clock. |
Selected CDR reference clock frequency |
Device Dependent |
Specifies the frequency of the clock input to the CDR. |
PPM detector threshold |
+/- 1000 PPM | Specifies the maximum PPM difference the CDR can tolerate between the input reference clock and the recovered clock. |
Enable rx_pma_clkout port |
On/Off |
When you turn this option On, the RX parallel clock which is recovered from the serial received data is an output of the PMA. |
Enable rx_is_lockedtodata port |
On/Off |
When you turn this option On, the rx_is_lockedtodata port is an output of the PMA. |
Enable rx_is_lockedtoref port |
On/Off |
When you turn this option On, the rx_is_lockedtoref port is an output of the PMA. |
Enable rx_set_lockedtodata and rx_set_locktoref ports |
On/Off |
When you turn this option On, the rx_set_lockedtdata and rx_set_lockedtoref ports are outputs of the PMA. |
Enable rx_pma_bitslip_port |
On/Off |
When you turn this option On, the rx_pma_bitslip is an input to the core. The deserializer slips one clock edge each time this signal is asserted. You can use this feature to minimize uncertainty in the serialization process as required by protocols that require a datapath with deterministic latency such as CPRI. |
Enable rx_seriallpbken port |
On/Off |
When you turn this option On, the rx_seriallpbken is an input to the core. When your drive a 1 on this input port, the PMA operates in serial loopback mode with TX data looped back to the RX channel. |
The following table lists the best case latency for the most significant bit of a word for the RX deserializer for the PMA Direct datapath. PMA Direct mode is supported for Arria V GT, ST, and GZ devices only.
FPGA Fabric Interface Width |
Arria V Latency in UI |
---|---|
8 bits |
19 |
10 bits |
23 |
16 bits |
35 |
20 bits |
43 |
64 bits |
99 |
80 bits |
123 |
The following table lists the best- case latency for the LSB of the TX serializer for all supported interface widths for the PMA Direct datapath.
FPGA Fabric Interface Width |
Arria V Latency in UI |
---|---|
8 bits |
43 |
10 bits |
53 |
16 bits |
67 |
20 bits |
83 |
64 bits |
131 |
80 bits |
163 |
The following table shows the bits used for all FPGA fabric to PMA interface widths. Regardless of the FPGA Fabric Interface Width selected, all 80 bits are exposed for the TX and RX parallel data ports. However, depending upon the interface width selected not all bits on the bus will be active. The following table shows which bits are active for each FPGA Fabric Interface Width selection. For example, if your interface is 16 bits, the active bits on the bus are [17:0] and [7:0] of the 80 bit bus. The non-active bits are tied to ground.
FPGA Fabric Interface Width |
Bus Bits Used |
---|---|
8 bits |
[7:0] |
10 bits |
[9:0] |
16 bits |
{[17:10], [7:0]} |
20 bits |
[19:0] |
40 bits |
[39:0] |
64 bits |
{[77:70], [67:60], [57:50], [47:40], [37:30], [27:20], [17:10], [7:0]} |
80 bits |
[79:0] |