766 - SERDES can run at either full-data-rate mode or half-data-rate mode What is the difference between the two?

With the same reference clock frequency, if the SERDES is configured to half-data-rate mode, the SERDES data rate is only half of the data rate supported in the full-data-rate mode. It is useful when different rates are used for different channels in one SERDES quad.

For LatticeSC/M, only full-data-rate mode is valid.

For LatticeECP2M, users can select "Full Rate" or "Half Rate" in "Channel Rate" option in the GUI, and they can also be changed by the registers "RATE_MODE_TX" and "RATE_MODE_RX" through SCI interface of SERDES at debugging.

For LatticeECP3, there are two ports named tx_div2_mode_chx_c and rx_div2_mode_chx_c(x means 0,1,2 or 3 for the four channels), which are used to configure the rate mode('0' for full-data-rate mode and '1' for half-data-rate mode) for the corresponding transmitted and received channels.

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766 - SERDES can run at either full-data-rate mode or half-data-rate mode What is the difference between the two?

766 - SERDES can run at either full-data-rate mode or half-data-rate mode What is the difference between the two?

Related Articles

263 - What is the difference between Quad Based Protocol Mode and Channel Based Protocol Mode?

768 - Can SERDES use different configurations and different reference clock frequencies to support the same data rate?

2533 - LatticeECP2M/ECP3: How can I&nbsp;access the&nbsp;full rate recovered&nbsp;clock&nbsp;to sample the receive data&nbsp;in a Lattice X1 Native PCIe IP targeting either LatticeECP2M or LatticeECP3 devices?

6965 - Serdes/PCS: How to know if the two SerDes data rates can be generated with the same reference clock frequency?

1179 - When using the Lattice FPGA PCS/SERDES QUADS in 10-bit Raw SERDES mode, how do I do interpret the 10-bit 8b10 encoded RX DATA?

2533 - LatticeECP2M/ECP3: How can I access the full rate recovered clock to sample the receive data in a Lattice X1 Native PCIe IP targeting either LatticeECP2M or LatticeECP3 devices?