Has it really been that long since I updated this thread :eek
A few things have happened...
I had a few computer problems and, in early June, I lost my latest sketch - long story, don't ask Anyway, I am pretty sure I have got back to where I was and the sketch is close to being finished.
As you may remember, this controller is being designed to control 10 separate channels. Whilst the Arduino Mega has 15 PWM pins, only 6 are readily accessible, due to the LCD shield, which leaves us a few short. I have also been mindful of the fact that the Arduino/Screen is likely to be remote from the LED drivers and we don't want 12+ wires going between the components - I have been planning on using some 8 core Cat5 cable for this purpose.
So, I have been planning on using a TLC5940 IC which operates over the Serial bus and provides 16 PWM channels - I already had some of these and have been designing the sketch around this solution.This requires 5 wires + 5v + Ground and so I would have one extra wire to use for a temperature sensor.
After quite a few hours trying to work out the best way do the layout on some vero board I came up with this
And found the time to solder up a board on the weekend.
I had also purchased a mini board from Adafruit quite some time ago which incorporates a PCA9685 IC - this also provides 16 PWM channels but operates over the i2c bus which only requires 2 wires + 5v + Ground. This was always going to be a better solution but I was mindful of the extra expense - this chip only comes in a Surface Mount format (i.e. tiny) so the mini board was the only way to use it . After much deliberation (or maybe it was procrastination) I have made the decision to ditch the TLC5940 and go with the PCA9685.
This was done for 2 reasons - making the vero board with the TLC5940 and associated components was time consuming and using this IC would limit the ability of anyone to put together this controller themselves. Yes, I could have made up the board for anyone wanting one but I think I would quickly tire of that :rolleyes. By using the mini board anyone can buy it if they want too.
The board is available from http://www.adafruit.com/products/815 and costs around US$15 + postage. I have ordered a number of these to get a few controllers up and running. Unfortunately, the fall in the AUD over recent weeks has made this a bit more expensive than it might otherwise have been.
This is a picture of my completed TLC5940 board together with the Adafruit mini board
Hopefully, by the time these arrive I will have everything else finished.
Hopefully ......
A few things have happened...
I had a few computer problems and, in early June, I lost my latest sketch - long story, don't ask Anyway, I am pretty sure I have got back to where I was and the sketch is close to being finished.
As you may remember, this controller is being designed to control 10 separate channels. Whilst the Arduino Mega has 15 PWM pins, only 6 are readily accessible, due to the LCD shield, which leaves us a few short. I have also been mindful of the fact that the Arduino/Screen is likely to be remote from the LED drivers and we don't want 12+ wires going between the components - I have been planning on using some 8 core Cat5 cable for this purpose.
So, I have been planning on using a TLC5940 IC which operates over the Serial bus and provides 16 PWM channels - I already had some of these and have been designing the sketch around this solution.This requires 5 wires + 5v + Ground and so I would have one extra wire to use for a temperature sensor.
After quite a few hours trying to work out the best way do the layout on some vero board I came up with this
And found the time to solder up a board on the weekend.
I had also purchased a mini board from Adafruit quite some time ago which incorporates a PCA9685 IC - this also provides 16 PWM channels but operates over the i2c bus which only requires 2 wires + 5v + Ground. This was always going to be a better solution but I was mindful of the extra expense - this chip only comes in a Surface Mount format (i.e. tiny) so the mini board was the only way to use it . After much deliberation (or maybe it was procrastination) I have made the decision to ditch the TLC5940 and go with the PCA9685.
This was done for 2 reasons - making the vero board with the TLC5940 and associated components was time consuming and using this IC would limit the ability of anyone to put together this controller themselves. Yes, I could have made up the board for anyone wanting one but I think I would quickly tire of that :rolleyes. By using the mini board anyone can buy it if they want too.
The board is available from http://www.adafruit.com/products/815 and costs around US$15 + postage. I have ordered a number of these to get a few controllers up and running. Unfortunately, the fall in the AUD over recent weeks has made this a bit more expensive than it might otherwise have been.
This is a picture of my completed TLC5940 board together with the Adafruit mini board
Hopefully, by the time these arrive I will have everything else finished.
Hopefully ......