hi, i am using a lpc2378 board with the ethernet PHY chip dp83848i, And also i am using the sample code provided by keil for ethernet transmission.. In that code Tx_only part is working fine... But in Rx_bouce, the interrupt which is to be generated when a packet is recieved by the lpc2378 from PHY, is not getting generated.And also the voltage of the signal out of PHY is 1.8volts with spikes at a range of 3.3v In the Tx_only program we got the data out from lpc2378 at 3.3v Dont know what the problem is!!!! why recieve part is not working!!!!! Please Some one help me out... its urgent.. THANKS IN ADVANCE..
Gayathri.K
Thank you for the response. This may not be possible since we are not sharing these ENET_RXD0 & ENET_RXD1 pins with any other function. Also, i wanted to clarify that this is the RMII output of PHY which is coming to LPC2378 at ENET_RXD0 and ENET_RXD1.Could there be any problem on the PHY chip side? regards, Gayathri
"This may not be possible since we are not sharing these ENET_RXD0 & ENET_RXD1 pins with any other function."
Maybe not intentionally, but have you made sure that you haven't intentionally missed changing the pin configuration from GPIO to ENET_RXD0/ENET_RXD1?
The fact is that the signal levels behaves as if you have two outputs colliding. When both outputs wants 3.3V, all is fine. When one output wants 3.3V and the other wants 0V, you will get some voltage in between - a bit depending on how strong the two outputs are.
or some other hardware fault.
Thanks for your reply.. I will verify the Pins and Let you know.
Regards, Gayathri.K
Yes. It can also happen if there is a solder bridge connecting two outputs.
kindly clarify whether a RMII signal of 3.3v is essential at the input of LPC2378 to generate the recieve interrupt. or what is the minimum voltage level needed to recognize a valid data.
Thanks in advance, Gayathri.k
look for holes near the track.
look for volts leaking away.
That will be clearly stated in the Datasheet!
Thank you so much for all your replies.. we got it working. Actually the problem is, there was a solder bridge shorting RX_D1 and RX_D0, which was pulling the voltage of the data down.
Thanks and Regards, Gayathri.k