How to draw this box representing a system with arrows indicating inputs and outputs?

Question

I need to draw a picture, the picture is showed below. Which package is better to draw it,TikZ? Actually I need integrate the latex code into my software program, and the input, output and variable are changeable according to the parameters in the program, for instance, if there are only two input parameter, then the picture just show two inputs. And the Legend part, since it is fixed, may be used as an attachment?

The program part I can think about it, but how to draw the picture in latex is really a challenge for me, anyone can help?

How to draw the black color arrow sign?(RTDB variable)

I try to use pifont package for the little black arrow. I checked \ding{253} is the one i want, but when i use it in my latex code, it showed like a fishbone, do you know what is the problem?

Answer 1

This is an attempts where pics skill is used, requiring tikz 3.0

Code

\documentclass[border=10pt]{standalone}%[12pt,twoside,a4paper]{book}
\usepackage{graphicx,wrapfig,tikz}
\usetikzlibrary{positioning,shapes}
\tikzset{myarrow/.pic = {
\begin{scope}[rotate=-90,scale=0.5]
\draw[fill=black] (-0.5,0) -- (0,0.5)--(0.5,0)--(0.5,1)--
(0,1.5)--(-0.5,1)--(-0.5,0) ;
\end{scope}},
mydot/.pic={
\draw[fill=black,inner sep=0.7pt] circle(5pt);},
myelliB/.pic={
\draw[fill=black,inner sep=0.7pt] ellipse (1em and 0.5em);},
myelli/.pic={
\draw[very thick,inner sep=0.7pt] ellipse (1em and 0.5em);},
rec/.style={draw,minimum height=3em,minimum width=15em,fill=yellow},
}

\begin{document}
\begin{tikzpicture}
\draw (0,0) rectangle (6,6);
\node[] at (3,3) {CMDA::ALDS};

% draw myarrows on the left side
\foreach \i [count=\j from 1] in {5,4,3,2,1} {
\pic () at (-0.5,\i) {myarrow};
\node[xshift=-2cm] at (-1,\i) {input\j};
}

% draw mydots at bottom
\foreach \i [count=\j from 1] in {5,4,3,2,1} {
\pic (b\i) at (\i,0) {mydot};
\draw[] (\j,0)--(\j,-\i)node[right] {variable\j};
}

% draw myarrows on the right
\foreach \i [count=\j from 1] in {5,4} {
\pic () at (5.5,\i) {myarrow};
\node[xshift=2cm] at (6,\i) {output\j};
}

%--------legend
\node[rec] (L) at (11,2){Ledgend};
\node[rec,below=0.1cm of L](L1){RTDB variable};
\node[rec,below=0.1cm of L1](L2) {in all variants};
\node[rec,below=0.1cm of L2](L3){in some variants};
\node[rec,below=0.1cm of L3](L4) {XP variable};
\pic[xshift=-2.3cm] at (L1) {myarrow};
\pic[xshift=-2.cm] at (L2) {myelliB};
\pic[xshift=-2.cm] at (L3) {myelli};
\pic[xshift=-2.cm] at (L4) {mydot};
\end{tikzpicture}
\end{document}