Problem with I2C on Espruino Pico

[espruino-discuss3]

Posted at 2015-07-17 by IllusionaryPersona

Ive recently tried to add the the Light Sensor BH1750 to the Pico but it doesnt seem to work regardless of what I try. I had already done this with my normal Espruino and it worked there.
Heres how I tried to set it up :

I2C1.setup({scl:B6, sda:B7});
var bh=require("BH1750").connect(I2C1, 0);

And thats the error message I get:

Uncaught InternalError: Timeout on I2C Write BUSY
 at line 1 col 45
...i2ca=b;this.i2c.writeTo(b,1);this.i2c.writeTo(b,3);this.acti...
                               ^
in function "c" called from line 1 col 33
{return b?new c(a,92):new c(a,35)}
                                 ^
in function "connect" called from line 1 col 41
var bh=require("BH1750").connect(I2C1, 0);
                                         ^

I have no Idea what I did wrong, so im looking forward to a newbee friendly answer.

[espruino-discuss3]

Posted at 2015-07-17 by @gfwilliams

Have you got the most up to date version of Espruino? process.env.VERSION should report 1v79. I know there were some issues with earlier versions.

If not, it could well be a wiring problem. I2C waits for a response, so if nothing is happening it could be:

• Power not getting to the module (I'd check with a meter - Bat is a battery input on the Pico, not an output) - most likely the issue if you were using on an Espruino board before
• SDA/SCL swapped or not connected
• Pullup resistors not on SDA/SCL

Hope that helps!

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Posted at 2015-08-06 by IllusionaryPersona

Sorry for my late answer,
I have tried all of the things you listed above and now I can set the BH1750 up correctly but if I try to use it, it still gives me an error, so i made a picture of my setup. Maybe you can find the problem with it.
Heres the code:

I2C1.setup({scl:B6, sda:B7});
var bh=require("BH1750").connect(I2C1, 0);
bh.start(2, 0);

function lux() { 
  var luxx = bh.read();
  console.log("lux=", luxx);
}

setInterval(lux,1000);

And here is the error message:

Uncaught InternalError: Timeout on I2C Read BUSY
 at line 1 col 53
...is.i2c.readFrom(this.i2ca,2),a=(a[0]<<8)+a[1];this.onetime&&...
                               ^
in function "read" called from line 2 col 22
  var luxx = bh.read();
                      ^
in function called from system

---

Attachments:

• IMG_20150804_163024.jpg

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Posted at 2015-08-06 by DrAzzy

Check your connections, usually that one means that one of the I2C lines is shorted to ground.

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Posted at 2015-08-07 by @gfwilliams

@fdufnews I have to delete posts - I just did it for you :)

One thing that strikes me is you connected the power for the module to pin B3 - the 4th pin in from the left. You probably meant to connect power to 3.3v, which is the 3rd pin in.