Internal 32-bit SDR Client-Side Interface
The mapping of lanes to data bits is shown in the following table. The lane
number is also the index of the control bit for that particular lane; for example,
tx_mii_c[2] and tx_mii_d[23:16] are the control and data bits, respectively for lane
2.
| Lane | tx_mii_d, rx_mii_d Bits |
|---|---|
| 0 | 7:0 |
| 1 | 15:8 |
| 2 | 23:16 |
| 3 | 31:24 |
Definitions of Control Characters
Reference is regularly made to certain XGMII control characters signifying Start, Terminate, Error, and others. These control characters all have in common that the control line for that lane is 1 for the character and a certain data byte value. The relevant characters are defined in the IEEE Std. 802.3 and are reproduced in the following table for reference.
| Data (Hex) | Control | Name, Abbreviation |
|---|---|---|
| 00 to FF | 0 | Data (D) |
| 07 | 1 | Idle (I) |
| FB | 1 | Start (S) |
| FD | 1 | Terminate (T) |
| FE | 1 | Error (E) |