static double ExtractSignalFromBytes(byte[] bytes, Message.Signal signal)
{
int startByte = (int)signal.StartBit / 8;
int startBit = (int)signal.StartBit % 8;
int numBits = (int)signal.BitSize;
Debug.Assert(numBits > 0);
Debug.Assert(signal.ByteOrder == Message.Signal.ByteOrderEnum.LittleEndian);
Debug.Assert(numBits < 64);
long totalInteger = 0;
bool negative = false;
int bitsConsumed = 0;
while (numBits > 0)
{
int bitsToConsume = Math.Min(numBits, 8 - startBit);
int mask = ((1 << bitsToConsume) - 1);
int v = bytes[startByte];
v >>= startBit;
v &= mask;
v <<= bitsConsumed;
totalInteger += v;
if (signal.ValueType == Message.Signal.ValueTypeEnum.Signed)
{
if (bitsToConsume == numBits)
{
int hibit = (1 << (numBits - 1));
if ((v & hibit) != 0)
{
negative = true;
}
}
}
bitsConsumed += bitsToConsume;
numBits -= bitsToConsume;
startBit = 0;
startByte++;
}
double totalDouble = totalInteger;
if (negative)
{
totalDouble -= (1 << bitsConsumed);
}
totalDouble *= signal.ScaleFactor;
totalDouble += signal.Offset;
return(totalDouble);
}
static double ExtractSignalFromBytes(byte[] bytes, Message.Signal signal)
{
UInt64 signalMask = 0;
for (int bit_index = (int)(signal.StartBit + signal.BitSize - 1); bit_index >= 0; --bit_index)
{
signalMask <<= 1;
if (bit_index >= signal.StartBit)
{
signalMask |= 1;
}
}
UInt64 signalValueRaw = 0;
for (int byte_index = bytes.Length - 1; byte_index >= 0; --byte_index)
{
signalValueRaw <<= 8;
signalValueRaw += bytes[byte_index];
}
signalValueRaw &= signalMask;
if (signal.ByteOrder == Message.Signal.ByteOrderEnum.BigEndian)
{
signalMask = ByteSwap64(signalMask);
signalValueRaw = ByteSwap64(signalValueRaw);
}
while ((signalMask & 0x1) == 0)
{
signalValueRaw >>= 1;
signalMask >>= 1;
}
double signalValue = signalValueRaw;
if (signal.ValueType == Message.Signal.ValueTypeEnum.Signed)
{
UInt64 signalMaskHighBit = (signalMask + 1) >> 1;
if ((signalValueRaw & signalMaskHighBit) != 0)
{
signalValue = -(Int64)((signalValueRaw ^ signalMask) + 1);
}
}
signalValue *= signal.ScaleFactor;
signalValue += signal.Offset;
return(signalValue);
}
