One of the programmable traffic pattern data modes is PRBS data mode. In PRBS data mode, the PRBS Data Seed can be programmed per data bit using the VIO interface.
The following are steps to program PRBS Data Seed (wait for at least one general interconnect cycle between each step):
- Set the
vio_tg_start
to 0 to stop ATG before reset deassertion. - Check the
vio_tg_status_state
to be TG_INSTR_START (hex0). - Set the
vio_tg_seed_num
andvio_tg_seed_data
with the desired seed address number and seed. - Wait for four general interconnect cycles (optional for relaxing VIO write timing).
- Set the
vio_tg_seed_program_en
to 1. This enables seed programming. - Wait for four general interconnect cycles (optional for relaxing VIO write timing).
- Set the
vio_tg_seed_program_en
to 0. This disables seed programming. - Wait for four general interconnect cycles (optional for relaxing VIO write timing).
- Repeat steps 3 to 8 if more than one seed (data bit) is programmed.
- Set the
vio_tg_start
to 1. This starts traffic generator with new seed programming.