open-source-silicon.dev

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Does anyone know, what this error means? I only have a small wishbone client with one 32 bit register that can be read and written... (The Register is internal and does not exit the chip)

It means one of the following:
• Your `FP_CORE_UTIL` and/or `PL_TARGET_DENSITY` are too high
• The area is too small or too rectangular

One handy thing might be to install openroad, then use the gui to inspect your design. Run `openroad -gui`, then open the DB file in `designs/sev_seg_shift_reg/runs/sev_seg_shift_reg/tmp/placement/8-resizer.odb`. You can select the "routing" heatmap on the left of the screen to see just how busy it is.

For example, here is a heatmap from a 32x31 register file I'm routing on GF180MCU.

I actually now worked around this issue... Since I only have one 32 Bit Register... I am going to put it on the logic analyzer anyway...