PMA Direct Bonding Mode
When you use multiple PMA Direct lanes together, it is called bonding; the number of lanes bonded together is the bonding mode.
- x1—Only one lane is used by itself (with its own settings)
- x2—Use two lanes together (lanes 0 and 1 or lanes 2 and 3); they share settings.
- x4—Use all four lanes in the same quad together; they share settings.
- x8—Use eight lanes together; they share settings. In this case, you are using all lanes two quads.
You choose the mode with the Bonding Mode drop-down list box in the PMA Direct block's Control Register tab.
The software checks that you have set the bonding mode for enough lanes in the same quad to create the bond, e.g., two lanes are in x2 mode or 4 lanes are in x4 mode. If you choose x8, then you need to have all eight lanes in two quads set to x8.
Each PMA Direct block instance has reference clock, data rate, and SerDes width settings. When the lanes are bonded together, they need to use the same settings. To make it easier to copy the settings to all lanes that are bonded together, the software shows the Apply Setting to <bonded lanes> in the Quad-Lane Settings dialog box. When you click the button, the settings are copied to the other bonded lanes.