W6100 read/write MAC

Question

Hello! When on startup I try to write MAC address I use the following SPI command: 41 20 04 01 02 03 04 05 06 And I get response: 01 02 03 00 00 00 00 00 00 But then I try to read it with: 41 20 00 00 00 00 00 00 00 And get the reply: 01 02 03 00 00 00 00 00 00 My SPI comms work as I get 01 02 03 at the start. But why the register is empty?

louis · Answer

Hello There’s no address inside the chip. You have to buy it separately and add address. Thank you

Himmat · Answer

Hello louis, I am facing same type of problem in my project where I am using valid MAC value “0x0013E1170001”. Steps are: 41 20 04 00 13 E1 17 00 01 And I get response: 01 02 03 00 00 00 00 00 00 But then I try to read it with: 41 20 00 00 00 00 00 00 00 And get the reply: 01 02 03 00 00 00 00 00 00 Please let me know what can be the issue? Thanks, Himmat

Welocs · Answer

Hi, your SPI stream is correct. You address 0x4120 (first byte of SHAR), Bank 0 (common registers) and you try writing variable length (0x04) and then reading variable length (0x00). I had issues with my breadbord wirings, where i thought, it was software (read my thread about this). Try reading the CIDR and VER registers to verify your SPI is working properly. What is your SPI speed?