I have successfully tested my set up (a PIC MCU development board) with wiz850io board. However, I made my own PCB with the W5500 chip and it is not working with the same set up. Using oscilloscope I monitor all the SPI signals and all seem fine except MISO; MISO is always low. Also I wire LINKLED to an LED and it is always HIGH.
I also probe the XI and XO pins and do not see any oscillation, they are always at 0V. Is the crystal not functioning and cause this problem? I use this crystal: ECS-250-10-37BQ-CTN-TR with two 12pF C0G/NP0 capacitors. This is the schematic:
Putting probes (x10) onto crystal will change the capacity and may distort the waveform you see. But you say you see nothing, and it must not be normal. Check your circuit against reference one. Check layout. Use microscope and inspect the quality of assembly. Ensure there’s no stupid mistake in the nominals of the components used. Ensure proper power provided to the chip’s circuit. Under normal conditions, when you attach live network cable to the device, link LED must turn on (but mind W5500 does not support MDIX).
@Eugeny is it possible that it cannot connect to the network due to a malfunction crystal?
Are W5500 to Ethernet and W5500 to MCU two independent circuits? i.e. if there is something wrong with one side, the other side can still function normally.
Hi
We have changed the method of soldering the circuit board and used blow soldering. The temperature is controlled below 300 ℃, and the W5500 can work normally