This input specifies how many tokens are to be added to the bucket after each
interval. A token is equal to 1 byte. This value must be greater than 0. The value of
this input should not be changed when
ctl_tx_rlim_enable is a value of
1.Note: This value should be
calculated based on the desired rate and the value in
ctl_tx_rlim_intv.Example: Programming the rate limiter assuming the following:
- The local bus clock frequency is 200 MHz.
- BurstMax is 256 bytes.
- The transmission rate is to be limited to 16 Gbits/s (or 2 Gbytes/s).
- The interval is arbitrarily chosen to be 16 local bus clock cycles.
The value for ctl_tx_rlim_delta is:
= (Byte Rate × Interval) / Local bus Frequency
= (2e9 × 16) / (200e6)
= 160 bytes
The value for ctl_tx_rlim_max must be 256 or greater.
Different values result in a different shaping of traffic. Simulations must be done to
select the proper value to get the desired packet rate.