Type: Answers

Type: Errata

Area: Intellectual Property



Critical Warning Messages When Local Loopback is Enabled

Description

If you enable local loopback on the MAC functions’s MII, GMII, or RGMII, the Quartus II software displays the following warning messages when you compile the designs:

Critical Warning: "mixed_port_feed_through_mode" parameter of RAM atom altera_tse_mac:altera_tse_mac_inst|altera_tse_top_gen_host:top_gen_host_inst|altera_tse_top_w_fifo_10_100_1000:U_MAC_TOP|altera_tse_loopback_ff:U_LBFF|altera_tse_a_fifo_24:U_LBFF|altera_tse_sdpm_altsyncram:U_RAM|altsyncram:altsyncram_component|altsyncram_o4e1:auto_generated|ram_block1a8 cannot have value "old" when different read and write clocks are used. Critical Warning: "mixed_port_feed_through_mode" parameter of RAM atom altera_tse_mac:altera_tse_mac_inst|altera_tse_top_gen_host:top_gen_host_inst|altera_tse_top_w_fifo_10_100_1000:U_MAC_TOP|altera_tse_loopback_ff:U_LBFF|altera_tse_a_fifo_24:U_LBFF|altera_tse_sdpm_altsyncram:U_RAM|altsyncram:altsyncram_component|altsyncram_o4e1:auto_generated|ram_block1a7 cannot have value "old" when different read and write clocks are used.

You may safely ignore the warning messages.

This issue affects all designs with local loopback enabled on the MAC’s MII, GMII or RGMII.

Workaround/Fix

No workaround.This issue will be fixed in a future version of the Triple-Speed Ethernet MegaCore function.