Frames from the receive pipeline can be stored in onboard SDRAM before transferred to the host memory, if needed, in order to await available host memory transfer.
Total memory size
The total memory size for all buffers in the onboard SDRAM is:
- NT200A01: 12 Gbytes
- NT100E3-1-PTP: 8 Gbytes
- NT80E3-2-PTP: 8 Gbytes
- NT40A01: 4 Gbytes
- NT40E3-4-PTP: 4 Gbytes
- NT20E3-2-PTP: 4 Gbytes
Protection of frames in onboard memory
Frames stored in the onboard SDRAM are protected by a CRC, in order to detect any data error. One or more frames are discarded in case of any CRC error, depending on the error type.
The number of discarded frames can be derived from the ingress and egress counters, once the traffic is stopped and the SDRAM is emptied.
SDRAM fill level events
Four specific SDRAM fill levels can be defined in the ntservice.ini file (see DN-0449). If the SDRAM is filled above one of these levels, an event is triggered. If the fill level decreases below one of these levels minus 10%, an event is triggered.