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[on:]

Hi folks,

    Relative Newbie here. I have some device designs I'm in the process of realizing, and in the process of edumacating myself, I seem to come up with more questions than answers as I go. With the help of friends, I have learned a considerable amount over the course of the last year, but there's considerably more to learn before I can realize even the first of my designs.

Q1 : Is it not typical or even possible with Arduino to have an object oriented firmware ? Processing seems to be the default sketch language within the Arduino world, and seems procedural and not OOP. I would Love to hear common directions people take their projects in regarding firmware authoring. I'm experimenting, but at embryonic levels.

Q2 : My first project utilizes 16 RGB LEDs, 48 single color LEDs, 64 buttons, an LCD Display, digital pot, and a data slider. I am looking at using Schmartboard for 2 STP24DP05 surface mount LED drivers for the RGB LEDs, and two more for the remainder of the LEDs. I understand they incorporate the Shift Registers as well as the LED drivers, so they seem ideal for my purposes. My intent is to daisy-chain them together. Unfortunately, I don't know what influence the frequency of 30MHz has over the circuit design. Does it matter in the firmware ?

Q3 : For the buttons, the SR's I intend to use are SN74HC165N's, but I believe 74F151's have been mentioned as well. I do not know the reasons I would choose one over the other. Again, I would daisy-chain them to get the full 64 button assignments. Care to inform and influence my decision one way or the other ?

 There are so many areas in which I have not yet boldly gone. I have a definite idea of the interface (mostly buttons and LEDs), but how can it all work at the same time in a procedural setting (as opposed to OOP) ?

I'm listening and learning,
GDR

[Reply #1 on:]

Is it not typical or even possible with Arduino to have an object oriented firmware ?

I would lean towards not "not typical."  Generally, microcontroller control things which tends to be procedural.  The Arduino language is baed on C++.  To me, it could make sense to have an object as a data structure.  However, I doubt I would ever implement a MVC model.

I don't know what influence the frequency of 30MHz has over the circuit design

The shift register you are using might be capable of receiving data up to 25MHz (not sure where 30 is coming from), but the Arduino is certainly not capable of transmitting data that fast.

SN74HC165N's, but I believe 74F151

The 165 is a shift register.  The 151 is a multiplexer.  The shift register will give you the status of all of its Inputs during a single read-out operation.  With a multiplexer you tell it which specific input you are interested in.  I imagine the code and hardware implement is roughly the same.