WizFi210 SPI Issue



i’m trying to connect my WizFi210 to my STM32F407VG using a SPI connection. From the connection site everything seems to be working correctly as my scope/logic analyzer decode the right data I’m sending to the device. But it only send me a 0xF5 followed by zeros all the time. Some seconds after reboot the GPIO19 (IRQ) pin goes high and never get back to low, independendly how many clocks I gave to the CLK line. Does the device need some special setup? I used the SPI firmware which I get from your support.

Thanks for any help



Hello Jacop

If you get 0xF5 from WizFi210-SPI, I think that there is no problem about h/w.

According the below, 0xF5 means <SPI_IDLE>.

And there is some sample source about SPI-master based on STM32xxx.

I attached it, please refer to it.
WizFi210_SPI_App.zip (378 KB)



i solved the problem by myself: The NSS line must be HIGH for some us between every byte. And between NSS to-low transition and the start of the clock the device also needs a delay of a couple of SPI clock cycles. Due this limitations the SPI firmware is not really usefull because in this case the maximum data troughput is about 100 kb/s which is less than the simple 115.2kbaud of the UART firmware.



Yes, you’re right.

If you want a high speed data transmission and no data loss, it’s better UART than SPI.
(While SPI can’t support data flow control, UART can use flow control, CTS/RTS.)

If you apply a CTS/RTS in UART, WizFi210 UART can support 921.6Kbps buad rate without data loss.