“This is a good way of getting text into an IoT device or simply to provide a bunch of push-button inputs. The firmware in the Mega8A simply provides the latest keypress on every I2C byte read.
On the downside, the SMT switches are very fiddly without keycaps. Some sort of membrane cover option would be good. There is currently no support in ESPHome to use this as a KeyProvider component so you'll have to write your own. There's no interrupt output so the I2C master has to poll the device faster than the user presses the keys.
However, there is access on a 0.1" header row to reprogram it so you could, for example, change it to a TTL-level UART output to one of the Grove pins instead so that a UART at the other end could be event driven.”
“This is a great add on to be able to test software using buttons as triggers over the I2C interface. It is a little fiddly however very well made and a great piece of hardware.”
“Works great! There's a handy RGB led which indicates Caps, Fn and Sym lock. The buttons are really sturdy - they're not your normal surface mount buttons they are full metal and work great. The manufacturer only has CPP examples so here's one for micropython!”
