Espruino with Glediator & LED matrix

[espruino-discuss2]

Posted at 2015-11-15 by Owen

I'm trying to use Espruino as the controller to take LED matrix data from the Glediator over USB and output it onto an RGB LED matrix.
The Matrix is made up on 16x8 WS2812B pixels. I've attached the example code from Glediator for using an Arduino as the controller which I've tried ported to JS (see below).
I've tried using the example USART code from here: http://www.espruino.com/USART along with other code I found on the forum but so far nothing has worked. Is there something I'm missing in the code below? I'm unsure if data is being received but Espruino as I can't connect while data is being sent to check.

    function onInit() {
      SPI2.setup({baud:3200000, mosi:B15});
      var m = Graphics.createArrayBuffer(16,8,24,{zigzag:true,color_order:'bgr'});
      m.flip = function(){ SPI2.send4bit(m.buffer, 0b0001, 0b0011); }; // Not sure if I need this line?
      USB.setup(115200);
      portData();
    }

    function portData() {
      USB.on('data', function (data) {
        USB.print(data); 
        cmd+=data;
        var idx = cmd.indexOf("\r");
        while (idx>=0) { 
          var line = cmd.substr(0,idx);
          cmd = cmd.substr(idx+1);
          var s = "'"+line+"' = "+eval(line); 
          print(s);
          USB.println(s);
          idx = cmd.indexOf("\r");
          SPI2.send4bit(cmd, 0b0001, 0b0011);
        }
      });
    }

---

Attachments:

• WS2812_Glediator.ino

[gfwilliams]

Posted at 2015-11-16 by @gfwilliams

Well, I think the main one is that Espruino's 'console' works over the same USB connection as you're trying to send data on, so you want to move it out of the way. Maybe try Serial1.setConsole() in onInit.

When you do that you might want to avoid using save() though (just manually run onInit()), as then you'd have to reflash the board to get access to the console again.

You are also printing quite a lot of data - I guess it's for debugging, but that could slow things down a lot.

To help you out, you might want to get a USB-TTL converter and attach it to Serial1 (B6/B7 on the Pico). You can then interact with the Pico and debug it while using the USB connection to receive data.

... or you can do it the other way (might be easier to debug) - send the data from Glediator to the USB-TTL converter on Serial1, and then keep using USB to uploading code and debugging.

[espruino-discuss2]

Posted at 2015-11-16 by Owen

I do have a USB-TTL converter, I'll give that a good tonight after work.

[espruino-discuss2]

Posted at 2015-11-16 by Owen

I've tried a few different things but nothing fully working yet. I've confirmed that serial data is being correctly sent out of the PC, Espruino just can't seem to read it.
I have changed my setup to use a USB-TTL. The Espruino USB is now being use for code uploading and console. All serial data is being sent to the USB-TTL and then into Espruino on the following pins. I'm using the original Espruino board for now and my wiring for the USB-TTL Converter is RXD > C10 & TXD > C11
I don't think I can use A9&10 as I have a bluetooth module attached.

After running my test code .on('data' still isn't receiving anything. As a basic test I tried the following code with nothing connected and the results are strange, am I doing something wrong?

function onInit() {
  //Serial1.setup(115200);
  Serial3.setup(9600);
  Serial3.on('data', function (data) { console.log("<Serial3> "+data); });
  Serial3.print("Hello World");
  console.log('Code is running.');
}
onInit();

After uploading code:

>echo(0);
Code is running.
=undefined

Nothing is outputted?

After entering save():

Running onInit()...
Code is running.
<Serial3> 
<Serial3> 
> 

Serial3 is outputted but not the "Hello world"
If I set a baud rate of 115200 Serial3 isn't outputted.

[gfwilliams]

Posted at 2015-11-17 by @gfwilliams

I'm not quite sure I understand. You'd expect Hello World to appear on the terminal program connected to your USB-TTL - but it doesn't? Have you checked that the baud rate of the connected terminal program is set to the same baud rate you set for Serial3?

Or you've left C10/C11 completely disconnected and you were expecting things to be echoed back?

It might be worth trying:

Serial3.on('data', function (data) { console.log("<Serial3> "+JSON.stringify(data)); });

That'll make sure that if there are nonprintable characters, they get escaped so you can see them.

Are you using an up to date (1v81) firmware? Some of the older ones had issues with Serial3/4.

[espruino-discuss2]

Posted at 2015-11-17 by Owen

Part success!
I've got Serial3 receiving data, issue appeared to be that I needed to give the pins in Serial3.setup
I ran many tests and passed it simple test strings to confirm that it was working and the while() loop would wait until it saw \r
Now I've begun passing it the matrix data from Glediator and..part success. The serial data is being received and using SPI2.send4bit I push it out onto the matrix. But the matrix lights up crazy, see the photo below.

Now as crazy as it is, the movement of the pixels and overall colour does match that from Glediator so I'm thinking the issue is more to do with me not correctly finding the beginning of the data. If it is not \r what else could it be?
Or is there something else I'm missing completely? I've attached my full code below:

  function onInit() {
    SPI2.setup({baud:3200000, mosi:B15});
    var m = Graphics.createArrayBuffer(15,15,24,{zigzag:true,color_order:'bgr'});
    m.flip = function(){ SPI2.send4bit(m.buffer, 0b0001, 0b0011); };
    
    var cmd = "";
    Serial3.setup(1000000, {tx:C10,rx:C11});
    Serial3.on('data', function (data) {
      cmd+=data;
      var idx = cmd.indexOf("\r");
      while (idx>=0) {
        var line = cmd.substr(0,idx);
        cmd = cmd.substr(idx+1);
        idx = cmd.indexOf("\r");
        SPI2.send4bit(line, 0b0001, 0b0011);    
      }
    });
  }
  onInit(); 

[espruino-discuss2]

Posted at 2015-11-17 by DrAzzy

Can you confirm that serial is seeing sensible data? maybe console.log(line); in there?

[espruino-discuss2]

Posted at 2015-11-17 by Owen

I've tried console.log(line) but when Serial3 is being sent data USB don't respond. The only time I got something back from Espruino it was a "Out of memory" warning.

[espruino-discuss2]

Posted at 2015-11-17 by Owen

Maybe it's not an issue with detecting the line ending but rather then matrix encoding. Do you know what format SPI2.send4bit() expects?

[espruino-discuss2]

Posted at 2015-11-18 by DrAzzy

It expects an array of bytes which are to be sent.

[espruino-discuss2]

Posted at 2015-11-18 by Owen

Using an SD card I saved the raw data of "line" to a file and have attached it here. Does it make any sense to anyone?

Attachments:

• RAWdata.txt

[gfwilliams]

Posted at 2015-11-18 by @gfwilliams

The 'out of memory' error sounds like you're not getting a newline, so are just making a huge string with all the data from multiple frames?

Actually, if you look at that Arduino file you sent, it seems to me like it's sending binary data and is using a simple 1 as the 'new frame' character (line 110) - presumably it ensures that it just never sends '1' normally.

Try:

function onInit() {
    SPI2.setup({baud:3200000, mosi:B15});    
    var cmd = "";
    Serial3.setup(1000000, {tx:C10,rx:C11});
    Serial3.on('data', function (data) {
      cmd+=data;
      var idx = cmd.indexOf("\1");
      while (idx>=0) {
        var line = cmd.substr(0,idx);
        cmd = cmd.substr(idx+1);
        idx = cmd.indexOf("\1");
        SPI2.send4bit(line, 0b0001, 0b0011);    
      }
    });
  }
  onInit(); 

[gfwilliams]

Posted at 2015-11-18 by @gfwilliams

Just to add that you could also be having some electrical issues if you get flickering - I think there's a note on the WS2811 page about using a pullup resistor and putting SPI into Open Drain mode? It might be needed if you're running the panel off a separate 5v supply.

... finally I don't know if Glediator handles the zig-zag pattern of the LEDs? It could be a pain to try and re-order them quickly. About the only thing I can think is to use Graphics with drawImage of the image data you received.

[espruino-discuss2]

Posted at 2015-11-18 by Owen

Success! You're a genius Gordon \1 was it! It works perfectly and with great frame rates.
I had a problem with random colours appearing when powering the Espruino directly off 5V and not the PC but I fixed that by simple grounding the USB-TTL to the 5V supply.
https://www.youtube.com/watch?v=Yk55bTqTVDY

[gfwilliams]

Posted at 2015-11-19 by @gfwilliams

Wow, that works well! So is your finished code literally just what was posted above?

And glediator handles the zig-zag automatically?

[espruino-discuss2]

Posted at 2015-11-19 by Owen

I had a to change a few little bits. For example I had to remove the call to onInit(); other wise the serial on(data) was getting fired twice on boot which messed up the output.
I also added a frame per second counter for testing and I get a steady 25 fps!
My next task maybe to try and get this working over USB alone but if I need console access this might not be possible. maybe I could move console onto Bluetooth..
Here is the full code used in the video:

  var fps = 0;
  function onInit() {
    SPI2.setup({baud:3200000, mosi:B15});
    var cmd = "";
    Serial3.setup(1000000, {tx:C10,rx:C11});
    Serial3.on('data', function (data) {
      cmd+=data;
      var idx = cmd.indexOf("\1");
      while (idx>=0) {
        var line = cmd.substr(0,idx);
        cmd = cmd.substr(idx+1);
        idx = cmd.indexOf("\1");
        SPI2.send4bit(line, 0b0001, 0b0011);
        fps++;
      }
    });
    
    var fps = setInterval(function() {
      console.log('fps: ' + fps);
      fps = 0;
    }, 1000);
  }

[espruino-discuss2]

Posted at 2016-04-09 by Owen

Hi Gordon,
I understand the idea but can't get it to work. It is outputting mostly random colours and the idx.length looks too small. My guess is it's receiving the data but doesn't know where the frame begins or perhaps the frame break "\1" is being included in the output.
I've tweaked your code a bit to get it working but with the problems above.
PS. I've been running this code on both the Pico and orgional Espruino with the same results on both.

/**
Glediator settings
Driver: Glediator
Baud 115200
Colour order: GRB
Pixel order:  HS_TL
*/
var fps = 0,
    buf = new Uint8Array(15*15*3),
    bufIdx = 0,
    cmd = "";

function onInit() {
  SPI1.setup({baud:3200000, mosi:A7});
  
  Serial1.setup(115200, {tx:B6,rx:B7});
  Serial1.on('data', function (data) {
    
    buf.set(data, bufIdx);
    bufIdx += data.length;
    
    if (data.indexOf("\1") >= 0) {
      var idx = bufIdx + data.indexOf("\1");
      var line = new Uint8Array(buf.buffer, 0, idx);
      console.log(idx);
      
      SPI1.send4bit(line, 0b0001, 0b0011);
      buf.set(new Uint8Array(buf.buffer, idx, bufIdx-idx), 0);
      bufIdx -= idx;
      fps++;
    }
  });
    
  var fps = setInterval(function() {
    console.log('fps: ' + fps);
    fps = 0;
  }, 1000);
}

onInit();

This outputs the following:

  594  
  594  
  593  
  593  
  594  
  593  
  594  
  594  
  594  
  594  
  594  
  593  
  fps: 12  
  593  
  594  
  593  
  593  
  593  
  594  
  593  
  594  
  593  
  593  
  594  
  fps: 11  

[gfwilliams]

Posted at 2016-04-09 by @gfwilliams

The first thing I noticed was you changed:

    buf.set(data, bufIdx);
    var idx = bufIdx+data.indexOf("\1");
    bufIdx += data.length;

to

    buf.set(data, bufIdx);
    bufIdx += data.length;
    
    if (data.indexOf("\1") >= 0) {
      var idx = bufIdx + data.indexOf("\1");

Obviously that's going to change the value of idx, so is a good place to start :)

[espruino-discuss2]

Posted at 2016-04-09 by Owen

I changed that because idx will always been greater than -1 after the first loop because it's get added the value of bufIdx.

The output now is a very low number of idx, basically every bit of data received. The fps count jumps way up to over 200. See the example output below:

	fps: 232
	29
	34
	30
	29
	30
	29
	7
	0
	25
	28
	30
	29
	29
	30
	29
	29
	30
	29
	29
	30
	29
	29
	29
	28
	28
	29
	13
	0

[gfwilliams]

Posted at 2016-04-09 by @gfwilliams

Please can you change console.log so it outputs buf.length and line.length as well? And can you paste up the code you used and the results? It'd be handy to see the data that was in line too - but I imagine printing it all out might overwhelm the Espruino :(

Also, do you still get the FIFO_FULL errors? It might be that even with this, you still have the same problem.

[espruino-discuss2]

Posted at 2016-04-09 by Owen

I've attached the exact code I used and below is the console output.

	idx 4
	buf 1000
	line 4
	idx 109
	buf 1000
	line 109
	idx 2
	buf 1000
	line 2
	idx 109
	buf 1000
	line 109
	idx 2
	buf 1000
	line 2
	idx 109
	buf 1000
	line 109
	idx 4
	buf 1000
	line 4
	idx 111
	buf 1000
	line 111
	idx 4
	buf 1000
	line 4
	idx 110
	buf 1000
	line 110
	idx 4
	buf 1000
	line 4
	idx 110
	buf 1000
	line 110
	idx 2
	buf 1000
	line 2
	idx 110
	buf 1000
	line 110
	idx 4
	buf 1000
	line 4
	idx 110
	buf 1000
	line 110
	idx 5
	buf 1000
	line 5
	idx 110
	buf 1000
	line 110
	idx 4
	buf 1000
	line 4
	idx 110
	buf 1000
	line 110
	idx 4
	buf 1000
	line 4
	idx 109
	buf 1000
	line 109
	idx 3
	buf 1000
	line 3
	idx 110
	buf 1000
	line 110
	idx 2
	buf 1000
	line 2

With the attached code "line" is only 4 bits in length;

JSON.stringify(line) "new Uint8Array([37,0,37,32])"

Using the original working code I managed to get a complete frame of data in line which I've pasted below.

    >USB.print(JSON.stringify(line));
    "?\x00?D\x00DD\x00D?\x00?9\x0094\x004/\x00/*\x00*$\x00$ \x00 \x1B\x00\x1B\x17\x00\x17\x13\x00\x13\x0F\x00\x0F\f\x00\f\f\x00\f\x0F\x00\x0F\x13\x00\x13\x17\x00\x17\x1B\x00\x1B \x00 $\x00$*\x00*/\x00/4\x0049\x009?\x00?D\x00DD\x00D?\x00??\x00?D\x00DD\x00D?\x00?9\x0094\x004/\x00/*\x00*$\x00$ \x00 \x1B\x00\x1B\x17\x00\x17\x13\x00\x13\x0F\x00\x0F\f\x00\f\f\x00\f\x0F\x00\x0F\x13\x00\x13\x17\x00\x17\x1B\x00\x1B \x00 $\x00$*\x00*/\x00/4\x0049\x009?\x00?D\x00DD\x00D?\x00??\x00?D\x00DD\x00D?\x00?9\x0094\x004/\x00/*\x00*$\x00$ \x00 \x1B\x00\x1B\x17\x00\x17\x13\x00\x13\x0F\x00\x0F\f\x00\f\f\x00\f\x0F\x00\x0F\x13\x00\x13\x17\x00\x17\x1B\x00\x1B \x00 $\x00$*\x00*/\x00/4\x0049\x009?\x00?D\x00DD\x00D?\x00??\x00?D\x00DD\x00D?\x00?9\x0094\x004/\x00/*\x00*$\x00$ \x00 \x1B\x00\x1B\x17\x00\x17\x13\x00\x13\x0F\x00\x0F\f\x00\f\f\x00\f\x0F\x00\x0F\x13\x00\x13\x17\x00\x17\x1B\x00\x1B \x00 $\x00$*\x00*/\x00/4\x0049\x009?\x00?D\x00DD\x00D?\x00??\x00?D\x00DD\x00D?\x00?9\x0094\x004/\x00/*\x00*$\x00$ \x00 \x1B\x00\x1B\x17\x00\x17\x13\x00\x13\x0F\x00\x0F\f\x00\f\f\x00\f\x0F\x00\x0F\x13\x00\x13\x17\x00\x17\x1B\x00\x1B \x00 $\x00$*\x00*/\x00/4\x0049\x009?\x00?D\x00DD\x00D?\x00??\x00?D\x00DD\x00D?\x00?9\x0094\x004/\x00/*\x00*$\x00$ \x00 \x1B\x00\x1B\x17\x00\x17\x13\x00\x13\x0F\x00\x0F\f\x00\f\f\x00\f\x0F\x00\x0F\x13\x00\x13\x17\x00\x17\x1B\x00\x1B \x00 $\x00$*\x00*/\x00/4\x0049\x009?\x00?D\x00DD\x00D?\x00??\x00?D\x00DD\x00D?\x00?9\x0094\x004/\x00/*\x00*$\x00$ \x00 \x1B\x00\x1B\x17\x00\x17\x13\x00\x13\x0F\x00\x0F\f\x00\f\f\x00\f\x0F\x00\x0F\x13\x00\x13\x17\x00\x17\x1B\x00\x1B \x00 $\x00$*\x00*/\x00/4\x0049\x009?\x00?D\x00DD\x00D?\x00??\x00?D\x00DD\x00D?\x00?9\x0094\x004/\x00/*\x00*$\x00$ \x00 \x1B\x00\x1B\x17\x00\x17\x13\x00\x13\x0F\x00\x0F\f\x00\f"=undefined
> 

[gfwilliams]

Posted at 2016-04-11 by @gfwilliams

I'm not sure the code is attached - please could you try to attach it again?

And sorry - when I said buf.length, I actually meant bufIdx :)

[espruino-discuss2]

Posted at 2016-04-11 by Owen

Here is the full output for two seconds: http://pastebin.com/M5Gien3D
After doing some more research I don't think there is anything wrong with the code and that it's been optimised as much as it can be the problem is there just isn't memory to process so many pixels fast enough. "FIFO_FULL" keeps poping up if I try and send more than around 150 pixels at 25fps.

Attachments:

• Pico-code.js

[gfwilliams]

Posted at 2016-04-12 by @gfwilliams

So it works if you lower the data rate? Is it possible to just lower the Baud rate on Serial then?

Also, if you remove the print statements, that should help a lot.

The Pico has a 512 byte input buffer I think - I guess it's possible that so much data is arriving while the last data is being sent to the LEDs that it gets full up...

150 pixels * 24 bits = 3600, and each bit takes 1.25us to send, so that's 4.5ms. If you're receiving data at 1000000 baud then that's 100,000 bytes/sec, so in 4.5ms you're receiving 450 bytes.

Add some overhead for executing JS and you're dangerously close to overflowing that buffer... So the solution would either be to:

• Reduce the baud rate
• Somehow ensure that the transmitter left a gap in transmission while data was being sent to the LEDs.
• Compile your own Pico firmware with a larger input buffer (without actually making big changes, you could get up to 1024 bytes).

[espruino-discuss2]

Posted at 2016-04-12 by Owen

The slowest baud-rate Glediator has is 115200 which might still be too fast.
I guess it just comes down to too many pixels to process at once. In my 15x15 matrix that is 255 pixels.
225 * 24 bits = 5400 bits
5400 bits * 1.25us = 6.75ms

If I could get Glediator to pause after each frame to allow Espruino to shift out the data it might work better but I don't think that's possible. You can't even limit the frame-rate from Glediator which may also be causing problems.
Increasing the Picos input buffer size might work but I've no idea how to do that.

[gfwilliams]

Posted at 2016-04-12 by @gfwilliams

115200 would be a huge help - the maximum frame rate Glediator could send over that would be 51fps (20ms), but it only takes 6.75ms to send it to the LEDs - so I think you stand a good chance with that.

[gfwilliams]

Posted at 2016-04-12 by @gfwilliams

You could also try using USB, rather than serial. USB has some rate-limiting built in, so you shouldn't have the FIFO_FULL error.

To do USB, you just swap Serial1 to USB in your code, and add Serial1.setConsole() to move Espruino's console over to Serial1 (to get it out of the way of USB).

[espruino-discuss2]

Posted at 2016-04-13 by Owen

Success! I've got it running the full 225 pixels at 25fps!
I kept tweaking the code and optimising as must as I could with no real change even at 115200. Then I change Serial1 to USB and boom full board working at full fps.
Changing to USB doesn't make it easy to work with but now I have a plug-n-play matrix output stick.

[gfwilliams]

Posted at 2016-04-13 by @gfwilliams

Great! You can always do something like:

function onInit() {
  Serial1.setConsole();
  setTimeout(function() {  
    if (BTN.read()) USB.setConsole();
  }, 1000);
}

So if you've saved and want to debug again, you can just plug the board in with the button pressed down, and you'll get access to the console again.

[espruino-discuss2]

Posted at 2016-11-26 by user69728

Hi Owen, could you post the finished code? I am just starting with Espruino, LED Matrix projects and glediator, it would be wonderful not to reinvent the color wheel :-) Thanks!

[espruino-discuss2]

Posted at 2016-11-30 by Owen

Hi,
I think this is the working code but haven't tested it in a while. Read the comment at the top for the wiring, matrix and Glediator settings.
Let me know if that works or not. I was using the Pico but it shouldn't matter which espruino you use.

/**
Glediator settings
Driver: Glediator
COM6
Baud 1000000
Colour order: GRB
Pixel order:  HS_TL
*/
var fps = 0,
    buf = new Uint8Array(15*15*3),
    bufIdx = 0,
    cmd = "";

function onInit() {
  SPI1.setup({baud:3200000, mosi:A7});
  
  Serial1.setup(115200, {tx:B6,rx:B7});
  Serial1.on('data', function (data) {
    
    buf.set(data, bufIdx);
    bufIdx += data.length;
    
    if (data.indexOf("\1") >= 0) {
      var idx = bufIdx + data.indexOf("\1");
      var line = new Uint8Array(buf.buffer, 0, idx);
      console.log(idx);
      
      SPI1.send4bit(line, 0b0001, 0b0011);
      buf.set(new Uint8Array(buf.buffer, idx, bufIdx-idx), 0);
      bufIdx -= idx;
      fps++;
    }
  });
    
  var fps = setInterval(function() {
    console.log('fps: ' + fps);
    fps = 0;
  }, 1000);
}

onInit();