RE: LDR Camera #2 : Adding an 8x8 Dot Matrix LED Display

clem57 — Sat, 28 Sep 2019 02:36:47 GMT

Great job [mention:d25512d61e65470296ce2f82f47741ab:e9ed411860ed4f2ba0265705b8793d05]. If you would like a bit of grey scale, you could turn on 0-8 depending on the level of grey and this would look like a graph of darkness or lightness. I will show using just the 3 LDR. The others are the same method.

Gval = value from ldr #3 / 32; The result should be from 0 through 7... So 0-31 is 0, 32-63 is 1, etc. up to 255.

if (LDRvalue > threshold)

matrix.drawPixel(Gval, 3, 1);

else

matrix.drawPixel(Gval, 3, 0);

Clem

RE: LDR Camera #2 : Adding an 8x8 Dot Matrix LED Display

shabaz — Fri, 27 Sep 2019 20:57:47 GMT

Hi Dubbie,

Glad the display is coming in handy : )

Adafruit had some code, but it was slightly bloated, so I too wrote my own code. There is some slightly weird mapping, as no doubt you spotted! : )

Anyway, it sounds all sorted, otherwise see the Pocket Nim code from line 828 onward (not tested on Arduino, but the I2C specific stuff is isolated to the first two functions from that line onward, so those could be replaced).

For the code above, something like this might work (this could be improved too, it's just to reduce the code a bit).

[embed:dc8ab71f-3b98-42d9-b0f6-e21e02a0f8e2:3ef06e6b-9b7d-4651-b12d-db8be7f5e991:type=c_cpp&text=%23define+LED_ON+1%0A%23define+LED_OFF+0%0A%0A%0Avoid+loop%28%29+%7B%0A%0A%0A++int+i%2C+a%3B%0A++int+ldr_pin%5B%5D%3D%7BA0%2C+A1%2C+A2%2C+A3%2C+A4%2C+A5%2C+A6%2C+A7%7D%3B%0A++while%281%29%0A++%7B%0A++++matrix.clear%28%29%3B%0A++++for+%28i%3D0%3B+i%3C8%3B+i%2B%2B%29%0A++++%7B%0A++++++a%3DanalogRead%28ldr_pin%5Bi%5D%29%3B%0A++++++Serial.print%28a%29%3B%0A++++++Serial.print%28%22+%22%29%3B%0A++++++%0A++++++if+%28a%3Ethreshold%29%0A++++++%7B%0A++++++++matrix.drawPixel%280%2C+i%2C+LED_ON%29%3B%0A++++++%7D%0A++++++else%0A++++++%7B%0A++++++++matrix.drawPixel%280%2C+i%2C+LED_OFF%29%3B%0A++++++%7D%0A++++%7D%0A++++matrix.writeDisplay%28%29%3B%0A++++delay%28500%29%3B%0A++%7D+%2F%2F+end+while%281%29%0A++%0A%7D]