WizFi360 with SPI, sending CMD command like AT

Question

I am using WizFi360 with SPI interface. I am reading the answers from WizFi360 correctly. But, when I am sending “AT” command, then I obtain the answer “ERROR”. I think, that I am sending incorect bytes. Can you explain, what means the information on the picture? How can I send AT command in bytes? SPI_CMD841×549 67 KB Now I am sending: 0x91 0x04 0x00 0x41 0x54 0x0d 0x0a

austin · Answer

Hello @lentec AT CMD Phase should be set in units of 4 bytes. For example, when sending ‘AT’, the AT CMD Phase should be filled with ‘AT’ and the remaining 2 bytes should be filled with dummy data. In this case, fill in the CMD Length byte with 4 bytes length information, which is the value of ‘AT’ + dummy data length 2 bytes. The link below is a WizFi360 SPI example, so please refer to it. GitHub - wizfi/WizFi360-SPI-to-Uart-in-Nucleo

lentec · Answer

I have found this: WizFi360-SPI-to-Uart-in-Nucleo-master\Src\main.c, lines: 582-587 TX_len = len + 2; if ( TX_len % 4 ) TX_len = ((TX_len + 3)/4) << 2; and it works on many AT instructions. So, the answer is: SPI_CMD841×549 68 KB