Linux Ethernet Switch/Router Hat

The most obvious Hat to use HLK-7688A on is a Ethernet Switch or Router with SPI backbone support. I have ordered a dev unit so I can test out this possibility. The Ethernet switch part is very straight forward, I also see a very decent SPI, but I need to dig a bit more into that before I decide on wherever this is a path forward or not. An alternative is to use the two UART’s to a classic STM32F405 if that does not work out or even use a STM32F407 and connect on the 5th Ethernet, but now it gets more complicated. I am also a bit concerned about taking on a work-load that includes a Linux distribution. I seriously hope this can be limited to making apps and a easySPI driver.

MT77688AN have 2 SPI’s, of which one do not have half-duplex and I suspect that the other already is connected to a Serial Flash, so using SPI for easySPI might not be straight forward or possible at all. But, that is something I need to learn more about.

One of the dev kits for HLK-7688 is a switch/router, so it is quite easy to just get the SPI lines and see if I can do what I want. I will obviously have a size issue on the Hat, but I can get a minimum of 3 RJ45’s + I can get more if I use 5 pin Micro JST connectors only – lets see.

Leave a Reply