#Region Project Attributes
#AutoFlushLogs: True
#CheckArrayBounds: True
#StackBufferSize: 300
#End Region
Sub Process_Globals
'These global variables will be declared once when the application starts.
'Public variables can be accessed from all modules.
Public Serial1 As Serial
Dim myRandomNumber As Byte
Dim t As Timer
End Sub
Private Sub AppStart
Serial1.Initialize(115200)
Log("AppStart")
Delay(1000)
t.Initialize("t_tick", 50)
t.Enabled = True
End Sub
Sub t_tick
RunNative("getTrueRotateRandomByte", Null)
Log("myRandomNumber = ", myRandomNumber)
End Sub
#if C
const int waitTime = 16;
byte rotate(byte b, int r);
void pushLeftStack(byte bitToPush);
void pushRightStackRight(byte bitToPush);
byte lastByte = 0;
byte leftStack = 0;
byte rightStack = 0;
byte rotate(byte b, int r) {
return (b << r) | (b >> (8-r));
}
void pushLeftStack(byte bitToPush) {
leftStack = (leftStack << 1) ^ bitToPush ^ leftStack;
}
void pushRightStackRight(byte bitToPush) {
rightStack = (rightStack >> 1) ^ (bitToPush << 7) ^ rightStack;
}
void getTrueRotateRandomByte(B4R::Object* o) {
byte finalByte = 0;
byte lastStack = leftStack ^ rightStack;
for (int i=0; i<4; i++) {
delayMicroseconds(waitTime);
int leftBits = analogRead(1);
delayMicroseconds(waitTime);
int rightBits = analogRead(1);
finalByte ^= rotate(leftBits, i);
finalByte ^= rotate(rightBits, 7-i);
for (int j=0; j<8; j++) {
byte leftBit = (leftBits >> j) & 1;
byte rightBit = (rightBits >> j) & 1;
if (leftBit != rightBit) {
if (lastStack % 2 == 0) {
pushLeftStack(leftBit);
} else {
pushRightStackRight(leftBit);
}
}
}
}
lastByte ^= (lastByte >> 3) ^ (lastByte << 5) ^ (lastByte >> 4);
lastByte ^= finalByte;
lastByte = lastByte ^ leftStack ^ rightStack;
b4r_main::_myrandomnumber = lastByte;
// return lastByte;
}
#End If
