BlinkStick 8th blue LED not working (only pulse/morph, nodejs)

gabriel.annell · January 24, 2021, 5:42pm

I recently bought the blinkstick square and the blinkstick stick, and I have this weird issue.

The eighth blue LED on the stick does not illuminate when using the morph and pulse functions provided in the NPM (nodejs) blinkstick package. But on the square it works fine.

However, if I use setColor, the blue LED on the 8th leds works fine… and using the morph function through python, the blue led that didn’t seem to be working actually works.

I don’t really know what has happened but I feel like it is relevant to bring this up.

Has anyone else had this problem?

gabriel.annell · January 24, 2021, 6:55pm

Actually this seems to happen with the square as well, so probably either something is wrong in my code or the NPM package

gabriel.annell · January 24, 2021, 10:55pm

OK so I found the problem,

github.com

arvydas/blinkstick-node/blob/master/blinkstick.js#L611


* @param {Number} count How many LEDs should return
* @param {Function} callback Callback to which to pass the color values.
* @return {Array} Callback returns an array of LED data in the following format: [g0, r0, b0, g1, r1, b1...]
*/
BlinkStick.prototype.getColors = function (count, callback) {
   params = _determineReportId(count * 3);


   this.getFeatureReport(params.reportId, params.maxLeds * 3 + 2, function (err, buffer) {
       if (callback) {
           if (typeof(buffer) !== 'undefined') {
               buffer = buffer.slice(2, buffer.length -1);
           }


           callback(err, buffer);
       }
   });
};

At that line, there is an off-by one error that somehow messes up. Since I don’t know the gritty details, I can’t tell what is going on but removing the “-1” in the buffer.slice parameters fixed my problem

stapuft · March 25, 2021, 3:19am

so how did you fix this? did you just remove the -1 and compile a new .exe, or did you edit the current one with a hex editor like program?

gabriel.annell · March 25, 2021, 6:50pm

No, I wrote my own program with javascript. I don’t use the blinkstick client at all.