W5500 Sn_SR always stays 0x00, Sn_CR never clears

Question

Hello friends, I am having issues with my TCP server on a W5500. My SN_SR register always stays at 0x00 and the Sn_CR register never clears. I am able to ping the device on the network and SPI seems to be working correctly. I have written the following snippet of code in order to test the Sn_SR register: int1 done = FALSE; uint16_t timeout; do { timeout = 100; setSn_MR(sn, Sn_MR_TCP); setSn_PORT(sn, 5000); setSn_CR(sn, Sn_CR_OPEN); while(getSn_SR(sn) != SOCK_INIT) { if(--timeout == 0) break; delay_ms(100); } if(getSn_SR(sn) != SOCK_INIT) setSn_CR(sn, Sn_CR_CLOSE); else done = TRUE; delay_ms(10000); } while(!done); I am using a PIC24EP512 Thank you for reading, any help is greatly appreciated!

Eugeny · Answer

Mobius1: My SN_SR register always stays at 0x00 Socket closed Mobius1: and the Sn_CR register never clears You do not test for it in the code provided Mobius1: I have written the following snippet You must ensure you do preparations properly. You reset the chip using RESET pin per specification, and optionally perform software reset using MR. I am not 100% sure if that may be the case, but you should set basic properties for the networking communication like MAC address. Mobius1: and SPI seems to be working correctly. This is the second thing to prove after you ensure proper reset by reading VERSIONR register. If SPI does not work as expected, you may simply read/write to wrong locations within the chip causing undefined behavior.

Eugeny · Answer

Mobius1: I have now done a reset at the start of the program my version register reads 0x04. Byte order is confused for address. Hopefully mistake is in printf. Mobius1: This is how it is actual behaving Now compare address for Sn_CR in the datasheet with the address your program displays. If byte order is confused, you are trying to read location 0xa800, then 0xa801 etc. and of course you get garbage. You must provide chip with address and BSB/RWB/OM information before you can access the register. If 0xa8 is control byte, then you address “Socket 2 TX Buffer” space.

Mobius1 · Answer

uint8_t WIZCHIP_READ(uint32_t AddrSel) { uint8_t spi_data[4]; uint8_t spi_rData[4]; printf(“ WIZCHIP_READ: Entering function with address 0x%04X ”, AddrSel); // Construct SPI command (address phase) spi_data[0] = (AddrSel & 0x00FF0000) >> 16; spi_data[1] = (AddrSel & 0x0000FF00) >> 8; spi_data[2] = ((make8(AddrSel, 0) & 0x1F) << 3) | 0x00; spi_data[3] = 0x00; // Read data phase //select output_low(W5500_CS_PIN); //transfer spi_transfer(spi_data, spi_rData, 4); //deselcet output_high(W5500_CS_PIN); return spi_rData[3]; } void WIZCHIP_WRITE(uint32_t AddrSel, uint8_t data) { uint8_t spi_data[4]; printf(" WIZCHIP_WRITE AFTER ASSIGNMENT: Entering function with address 0x%04X ", AddrSel); output_low(W5500_CS_PIN); // Construct SPI command (address phase) spi_data[0] = (AddrSel & 0x00FF0000) >> 16; spi_data[1] = (AddrSel & 0x0000FF00) >> 8; spi_data[2] = ((make8(AddrSel, 0) & 0x1F) << 3) | 0x04; spi_data[3] = data; output_low(W5500_CS_PIN); spi_transfer_write(spi_data, 4); output_high(W5500_CS_PIN); } This is what my read and write functions look like

Mobius1 · Answer

Yeah my SPI data is complete junk. I’m not sure how I should go about writing a read and write function that accomplishes targeting the socket registers. The ioLibary code doesnt seem to be working correctly. It seems like the control byte is off. WIZCHIP_SOCKET_WRITE(0x5000, 0x01); to write 0x01 to socket register 5 ADDRESS HIGH BYTE: 00 ADDRESS LOW BYTE: 50 CONTROL BYTE: 04 WRITTEN BYTE: 01

Eugeny · Answer

Mobius1: WIZCHIP_SOCKET_WRITE(0x5000, 0x01); to write 0x01 to socket 3 register 5 WIZCHIP_SOCKET_WRITE(0x500 | (0x0d << 3), 0x01); or WIZCHIP_SOCKET_WRITE((chip_address << 8) | (bsb << 3), 0x01);

Mobius1 · Answer

This seems to be working ok for the write function, however read seems to be off. First set is write the second is read. I appreciate your help. ADDRESS HIGH BYTE: 00 ADDRESS LOW BYTE: 05 CONTROL BYTE: 6C WRITTEN BYTE: 01 ADDRESS HIGH BYTE: 00 ADDRESS LOW BYTE: 00 CONTROL BYTE: 68 THIS IS THE VALUE OF SOCKET 5: 03

Eugeny · Answer

Mobius1: This seems to be working ok for the write function, however read seems to be off. First set is write the second is read. I appreciate your help. I was wrong WIZCHIP_SOCKET_WRITE((chip_address << 8) | bsb, 0x01) because bsb is already <<3 in the functions. What we are doing now is not related to W5500, but relates to just C and code of the functions you currently have. Your task is providing address, bsb and data into there in proper format. Note you must use appropriate address and bsb per datasheet’s chapter 3 to address specific data.