Altera UG-01080 Guia do Utilizador Página 295

  • Descarregar
  • Adicionar aos meus manuais
  • Imprimir
  • Página
    / 484
  • Índice
  • MARCADORES
  • Avaliado. / 5. Com base em avaliações de clientes
Vista de página 294
Chapter 13: Arria V Transceiver Native PHY IP Core 13–9
Standard PCS Parameters
November 2012 Altera Corporation Altera Transceiver PHY IP Core
User Guide
Phase Compensation FIFO
The phase compensation FIFO assures clean data transfer to and from the FPGA
fabric by compensating for the clock phase difference between the low-speed parallel
clock and FPGA fabric interface clock. Table 1311 describes the options for the phase
compensation FIFO.
f For more information refer to the Receiver Phase Compensation FIFO and Transmitter
Phase Compensation FIFO sections in the Transceiver Architecture in Arria V Devices.
Standard PCS/PMA interface
width
8, 10,16, 20
Specifies the width of the datapath that connects the FPGA fabric
to the PMA. The transceiver interface width depends upon
whether you enable 8B/10B. To simplify connectivity between the
FPGA fabric and PMA, the bus bits used are not contiguous for
16- and 32-bit buses. Refer to Active Bits for Each Fabric
Interface Width for the bits used.
FPGA fabric/Standar d TX PCS
interface width
8, 10,16, 20,
32, 40
Shows the FPGA fabric to TX PCS interface width which is
calculated from the Standard PCS/PMA interface width.
FPGA fabric/Standar d RX PCS
interface width
8, 10,16, 20,
32, 40
Shows the FPGA fabric to RX PCS interface width which is
calculated from the Standard PCS/PMA interface width.
Enable ‘Standard PCS’ low
latency mode
On/Off
When you turn this option On, all PCS functions are disabled
except for the phase compensation FIFO, byte serializer and byte
deserializer. This option creates the lowest latency Native PHY
that allows dynamic reconfigure between multiple PCS
datapaths.
Table 13–10. General and Datapath Parameters (Part 2 of 2)
Parameter Range Description
Table 13–11. Phase Compensation FIFO Parameters
Parameter Range Description
TX FIFO mode
low_latency
register_fifo
The following 2 modes are possible:
low_latency: This mode adds 3–4 cycles of latency to the TX
datapath.
register_fifo: In this mode the FIFO is replaced by registers to
reduce the latency through the PCS. Use this mode for
protocols that require deterministic latency, such as CPRI.
RX FIFO mode
low_latency
register_fifo
The following 2 modes are possible:
low_latency: This mode adds 2–3 cycles of latency to the TX
datapath.
register_fifo: In this mode the FIFO is replaced by registers to
reduce the latency through the PCS. Use this mode for
protocols that require deterministic latency, such as CPRI.
Enable tx_std_pcfifo_full port On/Off
When you turn this option On, the TX Phase compensation FIFO
outputs a FIFO full status flag.
Enable tx_std_pcfifo_empty port On/Off
When you turn this option On, the TX Phase compensation FIFO
outputs a FIFO empty status flag.
Enable rx_std_pcfifo_full port On/Off
When you turn this option On, the RX Phase compensation FIFO
outputs a FIFO full status flag.
Vista de página 294
1 2 ... 290 291 292 293 294 295 296 297 298 299 300 ... 483 484

Comentários a estes Manuais

Sem comentários