I don't think there is an easy answer to the speed problem. Of course, having an onboard MAC is the best, but that loses the advantage of a standard external module, which is to save a lot of development time.
An SPI interface would be an improvement over UART, but there is no standard for async data transfer over SPI. You would need to adapt firmware to the module (I believe the WizNet modules have SPI), and/or put SPI code into the module. If RT5350 runs OpenWRT, there is an opportunity there.
USB is also a possibility, USB 2.0 has a 480 Mbit/s data rate, but unfortunately USB comes with a lot of protocol baggage. I think you could drive the USB pipes directly, but then you would need to invent a new lightweight protocol. USB is half-duplex, so you at least need some master/slave handshaking.
Another possible there is a custom FTDI chip, they have some user programmable devices.
What about wireless SD cards? Anyone tried those?
An SPI interface would be an improvement over UART, but there is no standard for async data transfer over SPI. You would need to adapt firmware to the module (I believe the WizNet modules have SPI), and/or put SPI code into the module. If RT5350 runs OpenWRT, there is an opportunity there.
USB is also a possibility, USB 2.0 has a 480 Mbit/s data rate, but unfortunately USB comes with a lot of protocol baggage. I think you could drive the USB pipes directly, but then you would need to invent a new lightweight protocol. USB is half-duplex, so you at least need some master/slave handshaking.
Another possible there is a custom FTDI chip, they have some user programmable devices.
What about wireless SD cards? Anyone tried those?
