Question about activity led

Question

Hi, I’ve ported an application from W5300 to W5500. I’ve seen that now, if you send an UDP packet, no matter the destination, the activity led won’t flash. By comparison, on the W5300 chip, the activity led will flash at any packet, UDP or TCP. The TCP packets will turn the activity led on alright, but not the UDP packets… It’s a fault or a characteristic ? Thanks, Alex

alexpescaru · Answer

UDP data is processed OK. TCP data is processed OK. The whole system is working perfectly. I am sending UDP packets of 230 bytes, at 1 second interval, to a true/routable IP (195.225.x.x type of address). The UDP packets are reaching the destination OK, without loss. So the logic/processing is OK. But when the UDP packet leaves the W5500, there is no activity/pulse on the act led. Also, on the same system, I have a small web server. When the web requests are arriving and responded, the act is flashing. So, for TCP packets, the led is OK. But not for UDP. Does it matter the size of the packet? Again, the UDP packets are 230 bytes in length. Thanks, Alex

hjjeon0608 · Answer

Hi, I think the connection has problem ACT pin to LED or LED has problem. Check this. Thanks.

alexpescaru · Answer

In both my previous posts I’ve said that the TCP packets will turn the led on, but the UDP packets will not. So the led is OK and so its connection. I’ve investigated further and found out the following. When an UDP packet is received, the led is blinking. But when sending UDP packets, the led is not blinking. So the problem is only when sending UDP packets. Otherwise, the led is functioning OK, as it supposed to do.