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Altera_Forum
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11 years ago

Tse mac

I am using ALTERA tripple speed ethernet ip core.My question is:-If rx_section_empty has crossed its threshold value and not coming down,will TSE MAC keep on sending pause frames ?????
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

Thanks for reply.

Yes i m using Altera TSE MAC with internal FIFO and i am using Ethernet tester to pump the data to my design.

While debugging my design i observed that:- till the time data available in Rx_fifo of MAC is going up and down to set threshold value of rx_septy_value in command config register,ALTERA MAC is sending pause frames with PAUSE quanta value(0xffff) followed by PAUSE quanta value(0x0000) to the Ethernet tester . But if data available in Rx_fifo of MAC have croseed the rx_septy_value ,then mac will send one pause frame with PAUSE quanta value(0xffff) followed by PAUSE quanta value(0x0000) to the Ethernet tester.Ethernet tester will not send the data for the received pause quanta value.Moment this value will expire Ethernet tester will resume transmitting and if i have not read the rx_fifo of the mac during this time ,then data_available in rx_fifo of mac will cross the rx_almost_full value.

So according to my observation this time ALTERA MAC is not sending PAUSE FRAMES.So my qusetion is:- ALTERA MAC will send pause frame only if data available in Rx_fifo of MAC is going up and down to set threshold value of rx_septy_value ,but if data available in rxfifo is continuously above rx_septy_value then ALTERA MAC will not be sending PAUSE FRAMES contiously?????

Also i unable to understand the purpose of holdoff_quatna register purpose.What if i write 0x00000000 in the holdoff_quatna regiseter.???

Please relpy me.