AN 687: Implementing QPI Using the Transceiver Native PHY IP Core in Stratix V Devices

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ID 683888
Date 12/17/2015
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1.2.1. Setting the Transmitter Driver to Tri-State

Use the procedure below to set the transmitter driver to tri-state using Streamer mode 3.

To set the transmitter driver to tri-state:

  1. Ensure that the transceiver reconfiguration controller is correctly connected to the Native PHY IP core.
  2. Enable the .MIF streamer module by selecting the Enable channel/PLL reconfiguration option in the transceiver reconfiguration controller.
  3. Write the logical channel number to address 0x38.
  4. Write the MIF mode 0xC to address 0x3A.
  5. Write the rtx_pdb address 0x25A to address 0x3B.
  6. Write the Control and status register with a value of 0xE to address 0x3A to initiate a read.
  7. Read address 0x3c.
  8. With the data obtained from step 7, perform a RMW with the 15-bit data pattern that selects the rtx_pdb bit.
  9. Write the data pattern generated from step 8 to address 0x3C.
  10. Write the Control and status register with a value of 0xD to address 0x3A.

    After changing rtx_pdb to 0 to set the transmitter driver in tri-state, tx_pma_rxfound will go high after asserting tx_pma_txdetectrx and tx_pma_qpipullup, if the RX link exists with a 42.5Ω termination, as shown in the following figure.



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