CertusPro-NX SerDes/PCS Usage Guide
Preliminary
Technical Note
FPGA-TN-02245-0.81
© 2020-2021 Lattice Semiconductor
135
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Field
Name
Access
Width
Reset
Description
selected source/interface for the Tx Path.
1’b1 – use rx_pcsmode_sel to override the MODESEL to
set the MPCS mode for the Tx path.
1’b0 – use the MODESEL to set the MPCS mode for the
Tx path.
Table A. 32. Tx Path Control [reg10]
Field
Name
Access
Width
Reset
Description
[7]
tx_pmfifo_dis
RW
1
1’b0
Phase Matching FIFO. Specifies the Phase Matching FIFO is
enabled or disabled (Tx lane-to-lane Deskew).
1’b1 – Phase Matching FIFO disabled.
1’b0 – Phase Matching FIFO enabled.
[6]
tx_bond_mask
RW
1
1’b0
Bond Mask. The banded channel mode is defined by
mc1_tx_bond_mode signal.
1’b1 – exclude this channel from bonded channel
group.
1’b0 – do not exclude this channel.
[5]
tx_dbus_20b
RW
1
1’b0
Bus Width. Specifies the internal data bus width for Tx
Path.
1’b1 – internal data bus is 20-bit width.
1’b0 – internal data bus is 10-bit width.
Note: this bit is not applicable for 64B/66B PCS mode.
[4]
enc_8b10b_dis
RW
1
1’b0
8B/10B Encoding Enable. Specifies the 8B/10B encoding is
enabled or disabled.
1’b1 – Encoding disabled.
1’b0 – Encoding enabled.
[3]
tx_fifo_dis
RW
1
1’b0
Tx FIFO Enable. Specifies the Tx phase compensation FIFO
is enabled or disabled.
1’b1 – Tx phase compensation FIFO disabled.
1’b0 – Tx phase compensation FIFO enabled.
[2]
tx_gear_en
RW
1
1’b0
Gearing Enable. Specifies the 2:1 Gearing is enabled or
disabled. This bit controls the 8B/10B path and PMA Only
path gearing logic, as well as the “tx_out_clk” for all PCS
modes.
1’b1 – Gearing is enabled.
1’b0 – Gearing is disabled.
Note: In 8B/10B PCS mode and PMA Only mode, the
output clock (tx_out_clk) is driven by the divided-by-two
clock, if this bit is set to “1”. In 64B/66B PCS mode, the
output clock (tx_out_clk) is driven by the clock with
doubled rate of default output clock, if this bit is set to
“1”.
[1]
tx_mpcs_rst
RW
1
1’b0
Soft resets the Tx Path not including the register space.
1’b1 – reset the Tx MPCS path.
1’b0 – do not reset the Tx MPCS path.
[0]
tx_mpcs_dis
RW
1
1’b0
TX Path Enable. Specifies the MPCS channel Tx Path is
enabled or disabled.
1’b1 – MPCS channel Tx Path is disabled.
1’b0 – MPCS channel Tx Path is enabled.
Table A. 33. 8B/10B Encoder Control [reg11]
Field
Name
Access
Width
Reset
Description
[7:1]
reserved
RSVD
7
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