I need to find the parts to make this work off of one board. I need 6 PWM pins for lights. I need a keypad or atleast a 4 button layout and a display of some sorts. 2x16 lcd?
Any ideas on some hardware thats light on the pin use? What would you use or suggest?
6 PWM - fine
4 push buttons -fine
One LCD - is 6 pins
So total of 16 pins. On most arduino's like the UNO you have 19 pins so what is the problem?
On most arduino's like the UNO you have 19 pins so what is the problem?
Those 19 pins would be 0 to 13 + A0 to A5? I took my shoes off and counted. Looks like 20 to me.
In addition to the pins mentioned, you might want to leave 0/1 unassigned as you can use it with Serial input to trace messages to USB (and receive inputs from the computer in debug mode). IIRC, pin 13 (which has the LED) can also be problematic in a few cases, since the LED has a resistor on it.
The simplest answer is get an Arduino Mega instead of an UNO.
However, using an i2c LCD (or i2c backpack) would reduce the number of pins to 2 for the LCD (A4 and A5). Wire - Arduino Reference
You can also put the push buttons on the i2c bus to reduce the number of pins (or use a resistor tree to combine the buttons into a single analogue input.
If you needed more PWM outputs, according to google, there are PWM extender chips (TLC5940), and the Arduino Cookbook (2nd edition) evidently has a chapter (7.14) on how to set it up. I couldn't read the chapter online.
mcreefer:
I need to find the parts to make this work off of one board. I need 6 PWM pins for lights. I need a keypad or atleast a 4 button layout and a display of some sorts. 2x16 lcd?Any ideas on some hardware thats light on the pin use? What would you use or suggest?
i2c gpio chips and simple cheap and plentiful, there are also plenty of them that will do PWM. Plenty more can deal with your keypad, debounce and send you an interrupt via a single GPIO if you don't feel like polling it. It's easy to get hundreds of IO's via just the 2 i2c port pins. They are also pretty easy to find as 5v through hole parts so simple to breadboard or add to a protoshield.
I forgot to mentionthe RTC as well.
Well that's two more so you still have two pins free before you need to consider any port expanders.
Grumpy_Mike:
6 PWM - fine
4 push buttons -fine
One LCD - is 6 pins
So total of 16 pins. On most arduino's like the UNO you have 19 pins so what is the problem?
Which LCD do you know of that uses 6 pins? All I find is 10 pins.
Which LCD do you know of that uses 6 pins
They all do.
All I find is 10 pins.
They can all work in a 4 bit data mode as well as an 8 bit data mode, so just 4 data and two control lines uses 6 pins.