the write of just one row gets the brightness from the duration it is on
Yes - in the devices I've used before like http://www.espruino.com/LPD6416 (or where I was driving an 8x8 display directly), they've been so bright that the time taken for the JS to execute has been long enough that it was about a perfect duration, even without setInterval. However I guess that could be different in your case.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
Yes - in the devices I've used before like http://www.espruino.com/LPD6416 (or where I was driving an 8x8 display directly), they've been so bright that the time taken for the JS to execute has been long enough that it was about a perfect duration, even without
setInterval
. However I guess that could be different in your case.