I'm still at a loss to know why you think the nRF24 would introduce an amount of latency that would matter.
As I said in Reply #3 I am sending data every 100 millisecs - would that meet your requirement?
If not, what is the maximum that you would consider acceptable?
A maximum of 1 second between sending button states and receiving LCD states would be acceptable. The reason for this is because when you hold down a button to change a value, it increments/decrements by 1, then a few seconds later 10, then 100. I don't want to accidentally change a value by a few 100, because then I have to go in the opposite direction where the same error might occur.
e.g. starting at 1, say I want a value of 455:
1 // button held down
455 ////////button released
755 ///// 3 seconds lag
I am now at 755 instead of 455, so now I have to go the opposite way:
400 // button released
100 // 3 seconds lag
The LCD shield I am using is this: adafruit RGB LCD shield, sorry I didn't post it before - I thought I had.
On one hand it seems like the addition of a pro micro (I have one lying around) to the LCD/buttons shield could simplify things, as I don't have much experience coding from datasheets etc. But on the other hand it seems a bit like an overkill.
I just don't understand how you would operate the nrf24L01 module and its ce, csn, sck, mo, mi, irq inputs on the LCD/buttons side without an arduino. I only know that sck is a clock signal, and I forgot what mosi and miso do. Obviously its possible but I am wondering if its too difficult with my current skill set.
Basically the LCD/buttons shield uses i2c to comminucate with an arduino, I want to make this wireless. What is the best/simplest way to achieve this? I am assuming that it is to add an arduino (pro micro for example) to the lcd shield and have the two arduino's communicate button/lcd states to each other.
If lag causes the undesirable scenario above then I might as well have the pro micro handle the menu/lcd/buttons system and send "commands" to the main arduino? But that might get complicated/annoying aswell. So then what approach should I take?