Reset Mysterious behave and startup and softreset

Question

We have a behavior with the reaset that we can’t explain. The activator for the Problem was that after startup i cant send UDP data to the LAN. After some test i found that i have to wait 2sec after open to send data. That was only the activator not the main problem. I belive it cant be a normal behavior for the system and so some further testing. Description of the system and test enviroment: The W5500 ist in a 100 Mbit LAN Network and connected to a switch. All the time the tests run the VCC was still present. The W5500 is connected to a STM32 µ Controller. The PMODE inputs are connected to GPIO pins of the µ Controller, as well the reset line. The reset will be handled according the datasheet. First test: All PMODE Pins are set to low. That means 10Mbit half duplex etc. After Reset i can see on the switch that there is somthing present, but no link. Thats OK and and to expect. The PHYCFGR shows 0xB9 that means 10Mbit/HAlf Duplex and Link. By the way the read back of the PMODE status id all one’s ??? So what i have done next because i will switch to 100 Mbit full duplex. a) The the PHYCFGR to 0x00 b) Set PHYCFGR the PMODE to 011 reset bit to 0 and OPMD to 1 (all together 0x58 or 0b01011000) c) Set PHYCFGR reset to 1 and still the PMODE to 011 reset bit to 0 and OPMD to 1 (all together 0xd8 or 0b11011000 ) d) i wait that rst becomes 1 e) i measure the time from that point until the the lower three bits from the PHYCFGR becomes 1. Result: it take approx 2 sec. By the way the read back of the PMODE status id all one’s ??? So it takes approx 2 sec after softreset that the link becomes stable. Second test: a) Set the PMODE Pins to 011 b) The Status aof the PHYCFGR register come adhoc stable c)… d) as above e) now the link is very quick stable after hard reset and soft reset So the resulting question is: I) Why it takes so a long time to switch to an other link rate? II) Whx is the readback of the mode in the PHYCFGR is every time all ones. Normaly i would save the GPIO Ports even so i like the flexibility with soft reset. Whats the solution or behavior. Thanks in advance

switzigmann · Answer

Correction : The second test needs for startup as well approx 2 sec to become an active link.(i have to overlook that ther was a 3sec delay before)