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Memory Mapped Interconnect Reset Net Polarity Conflict
I have developed a simple client Avalon Memory Mapped Interface custom IP block. The MM interconnect block automatically generated a width adapter component that is causing an LNT-30023 - Reset Nets with Polarity Conflict DRC. It is not affecting the functionality of my custom MM block, but I am still interested in understanding the root cause of this issue. Details to follow, thank you in advance for any help.
Custom Avalon Memory Mapped Interface consists of the following signals:
- clk
- reset_n
- [7:0] writedata
- write
- [7:0] address
- Various conduit signals
The master is the JTAG to Avalon Master Bridge which defaults to have 32bit address and writedata signals. For this configuration a merlin width adapter is automatically generated in the mm_interconnect block of the platform system designer.
Both the custom IP block and the JTAG to Avalon Master Bridge are connected to an low-assert (reset_n) Reset Bridge IP Block. The custom IP block is configured to be an low-assert reset. I was under the impression all generated MM interconnect IP would inherit the low-assert reset.
Instead my Design Assistant Summary declares the following DRC error: LNT-30023 - Reset Nets with Polarity Conflict. The detailed description is as follows, where <my_block> is a placeholder for my custom block name:
- Driver: u0|mm_interconnect_0|<my_block>_avalon_slave_0_cmd_width_adapter|use_reg
- Non-inverted signal: u0|mm_interconnect_0|<my_block>_avalon_slave_0_cmd_width_adapter|data_reg[16]|SCLR
- Inverted Signal: u0|mm_interconnect_0|<my_block>_avalon_slave_0_cmd_width_adapter|address_reg[1]|SCLR
2 Replies
- RichardT_altera
Super Contributor
You may refer to the user guide below to learn more about Reset Polarity and Synchronization in Platform Designer:
4.9. Reset Polarity and Synchronization in Platform DesignerIf your design is functioning as expected, it is acceptable to waive the DRC.
For additional information about the DRC rules, please search for the LNT-30023 using the following link:
Quartus® Prime Pro Edition Help version 25.3
Regards,
Richard Tan - RichardT_altera
Super Contributor
Let me know if further assistance is needed or if the solution worked for you.
Regards,
Richard Tan