Hi, IPG is defined as minimum back-to-back frames gap. What if there is a back-to-back frames came in with IPG http://www.opencores.org/forums/ethmac/attachments/20040125/407f5fd8/attachment.htm

Hi Edward The IPG is defined as 12 bytes in average! The TX should generated between 9-12 bytes IPG when running at full speed. The standard describe the recommend random algoritme. So the RX MAC must be able to handle a minimum IPG of 9 bytes. Due to the alloved differences in clock frequency of +/-100 ppm clock phy's may even drop one word of 4 IPG bytes. So the resulting average IPG of 12 bytes becomes a little lower in the real world. To be 100 % compatible in all cases a RX MAC must be able to handle a one time IPG of only 5 bytes -----Original Message----- From: ethmac-bounces@opencores.org [mailto:ethmac-bounces@opencores.org]On Behalf Of Edward Hsu Sent: 26. januar 2004 00:19 To: ethmac@opencores.org Subject: [ethmac] Need to check IPG http://www.opencores.org/forums/ethmac/attachments/20040126/bac0d977/attachment.htm

Hi Peter, Thanks for the info. --Edward _____ From: ethmac-bounces@opencores.org [mailto:ethmac-bounces@opencores.org] On Behalf Of Peter Sørensen Sent: Monday, January 26, 2004 2:26 AM To: List about open source Ethernet MAC core Subject: RE: [ethmac] Need to check IPG ethmac-bounces@opencores.org [mailto:ethmac-bounces@opencores.org]On Behalf Of Edward Hsu Sent: 26. januar 2004 00:19 To: ethmac@opencores.org Subject: [ethmac] Need to check IPG http://www.opencores.org/forums/ethmac/attachments/20040128/d360ca89/attachment.htm

Hi, Actualy the TX should send always 96 BT . it is true that IPG can shrink mainly when the packet go thourgh repeters but this is on the recive side. As for the PPM if your crystal is faster than you should always transmite with exactly 96 BT, if your crystal is slower you should remove single byte and not 4 bytes. since Eth packet are byte aligned. (even if you work in word width). Practicly you should not have problem with smaller IPG, and usualy the input fifo can handle IPG of 3 with no difficulty. have a nice day Illan -----Original Message----- From: Peter Sørensen [mailto:sorensen@vitesse.com] Sent: Monday, January 26, 2004 2:26 AM To: List about open source Ethernet MAC core Subject: RE: [ethmac] Need to check IPG ethmac-bounces@opencores.org [mailto:ethmac-bounces@opencores.org]On Behalf Of Edward Hsu Sent: 26. januar 2004 00:19 To: ethmac@opencores.org Subject: [ethmac] Need to check IPG http://www.opencores.org/forums/ethmac/attachments/20040311/413e9961/attachment.htm