Microsoft Small Basic

Program Listing: RCH738

List Program

' Floating-point viewer with segment LED
' Copyright (c) 2012 Nonki Takahashi. All right reserved.
'
' History :
' 0.1 2012/07/16 Created.
'
GraphicsWindow.Title = "Floating-point viewer 0.1"
GraphicsWindow.BackgroundColor = "Silver"
nFrac = 6 ' number of fractional digits
nExp = 2 ' number of exponential digits
x = 10 ' left position for segment LED
y = 10 ' top position for segment LED
w = 30 ' width of one segment LED
h = 60 ' height of segment LED
nDigits = nFrac + nExp + 4 ' 3 for a decimal point, E and two signs
GraphicsWindow.Width = 2 * x + nDigits * w
GraphicsWindow.Height = 3 * y + h + 20 ' 20 means height of textbox
GraphicsWindow.BrushColor = "Black"
oNum = Controls.AddTextBox(x, 2 * y + h)
InitLED()
digits = Array.GetAllIndices(seg)
Stack.PushValue("local", x)
For i = 1 To nDigits
n = digits[i]
DrawLED()
x = x + w
EndFor
x = Stack.PopValue("local")
typed = "False"

Controls.TextTyped = OnTextTyped
While "True"
If typed Then
typed = "False"
num = Controls.GetTextBoxText(oNum)
If Text.GetLength(num) > nDigits Then
Num2FP()
DrawFP()
Else
DrawNum()
EndIf
EndIf
EndWhile

Sub OnTextTyped
typed = "True"
EndSub

Sub InitLED
' return clrLED - colors for LED
' return seg - table for number to segments
' return segPos - each (relative) position of segment
' return segNames - array of segment names
' return nSegs - number of segments
clrLED = "Base=Black;On=Red;Off=#333333;"
seg[0] = "a=True;b=True;c=True;d=True;e=True;f=True;"
seg[1] = "b=True;c=True;"
seg[2] = "a=True;b=True;d=True;e=True;g=True;"
seg[3] = "a=True;b=True;c=True;d=True;g=True;"
seg[4] = "b=True;c=True;f=True;g=True;"
seg[5] = "a=True;c=True;d=True;f=True;g=True;"
seg[6] = "a=True;c=True;d=True;e=True;f=True;g=True;"
seg[7] = "a=True;b=True;c=True;f=True;"
seg[8] = "a=True;b=True;c=True;d=True;e=True;f=True;g=True;"
seg[9] = "a=True;b=True;c=True;d=True;f=True;g=True;"
seg["A"] = "a=True;b=True;c=True;e=True;f=True;g=True;"
seg["B"] = "c=True;d=True;e=True;f=True;g=True;"
seg["C"] = "a=True;d=True;e=True;f=True;"
seg["D"] = "b=True;c=True;d=True;e=True;g=True;"
seg["E"] = "a=True;d=True;e=True;f=True;g=True;"
seg["F"] = "a=True;e=True;f=True;g=True;"
seg["G"] = "a=True;c=True;d=True;e=True;f=True;"
seg["H"] = "b=True;c=True;e=True;f=True;g=True;"
seg["I"] = "c=True;"
seg["J"] = "b=True;c=True;d=True;"
seg["K"] = "a=True;c=True;e=True;f=True;g=True;"
seg["L"] = "d=True;e=True;f=True;"
seg["M"] = "a=True;b=True;c=True;e=True;f=True;h=True;"
seg["N"] = "a=True;b=True;c=True;e=True;f=True;"
seg["O"] = "c=True;d=True;e=True;g=True;"
seg["P"] = "a=True;b=True;e=True;f=True;g=True;"
seg["Q"] = "a=True;b=True;c=True;d=True;e=True;f=True;h=True;"
seg["R"] = "e=True;g=True;"
seg["S"] = "a=True;c=True;d=True;f=True;g=True;h=True;"
seg["T"] = "d=True;e=True;f=True;g=True;"
seg["U"] = "b=True;c=True;d=True;e=True;f=True;"
seg["V"] = "b=True;f=True;g=True;h=True;"
seg["W"] = "b=True;c=True;d=True;e=True;f=True;h=True"
seg["X"] = "b=True;c=True;e=True;f=True;g=True;h=True"
seg["Y"] = "b=True;c=True;d=True;f=True;g=True;"
seg["Z"] = "a=True;b=True;d=True;e=True;g=True;h=True"
seg["~"] = "a=True;"
seg["-"] = "g=True;"
seg["_"] = "d=True;"
seg["?"] = "a=True;b=True;g=True;h=True;"
seg["."] = "h=True;"
seg["!"] = "b=True;h=True;"
seg["/"] = "b=True;e=True;g=True;"
segPos["a"] = "x=0.2;y=0.05;w=0.6;h=0.05;"
segPos["b"] = "x=0.8;y=0.1;w=0.1;h=0.375;"
segPos["c"] = "x=0.8;y=0.525;w=0.1;h=0.375;"
segPos["d"] = "x=0.2;y=0.9;w=0.6;h=0.05;"
segPos["e"] = "x=0.1;y=0.525;w=0.1;h=0.375;"
segPos["f"] = "x=0.1;y=0.1;w=0.1;h=0.375;"
segPos["g"] = "x=0.2;y=0.475;w=0.6;h=0.05;"
segPos["h"] = "x=0.45;y=0.8;w=0.1;h=0.05;"
segNames = Array.GetAllIndices(segPos)
nSegs = Array.GetItemCount(segPos)
EndSub

Sub DrawLED
' param x, y - position
' param w, h - size
' param n - number 0..9
Stack.PushValue("local", i)
GraphicsWindow.BrushColor = clrLED["Base"]
GraphicsWindow.FillRectangle(x, y, w, h)
GraphicsWindow.BrushColor = clrLED["Off"]
For i = 1 To nSegs
If seg[n][segNames[i]] Then
GraphicsWindow.BrushColor = clrLED["On"]
Else
GraphicsWindow.BrushColor = clrLED["Off"]
EndIf
xs = x + segPos[segNames[i]]["x"] * w
ys = y + segPos[segNames[i]]["y"] * h
ws = w * segPos[segNames[i]]["w"]
hs = h * segPos[segNames[i]]["h"]
GraphicsWindow.FillRectangle(xs, ys, ws, hs)
EndFor
i = Stack.PopValue("local")
EndSub

Sub DrawNum
' param num
len = Text.GetLength(num)
If len > nDigits Then
num = "ERR1" ' Error 1 : overflow
TextWindow.WriteLine("ERR2:len=" + len)
len = 4
EndIf
Stack.PushValue("local", x)
For i = 1 To len
n = Text.GetSubText(num, i, 1)
DrawLED()
x = x + w
EndFor
For i = len + 1 To nDigits
n = ""
DrawLED()
x = x + w
EndFor
x = Stack.PopValue("local")
EndSub

Sub DrawFP
' param fp - floating point number
Stack.PushValue("local", num)
num = fp
DrawNum()
num = Stack.PopValue("local")
EndSub

Sub Num2FP
' param num
' param nFrac
' param nExp
' return fp
numAbs = Math.Abs(num)
sign = num / numAbs
exp = Math.Floor(Math.Log(numAbs))
If Text.GetLength(Math.Abs(exp)) > nExp Then
fp = "ERR2" ' Error 2 : exponential part overflow
TextWindow.WriteLine("ERR2:exp=" + exp)
Goto exit
EndIf
frac = Math.Floor(numAbs * Math.Power(10, nFrac - 1 - exp))
frac = frac / Math.Power(10, nFrac - 1)
fp = (sign * frac) + "E" + exp
exit:
EndSub