Template / ExtractBitField Protocol Frame
This command includes a bit field from the source data (phase 1) and converts it into an ASCII number. It can only be used after a preceding phase 1, see BitDataEnd.
The resulting number is returned with the most significant digits first. LSB-encoded source data will be converted automatically.
The following sample cuts bits 1-6, converts them to ASCII, and extends the number to 4 digits. This results in "0016".
ExtractBitField 0001 5 Unpack|BinToAscii 4
The next sample shows the difference between the MSB- and the LSB-first encoding. This command outputs "3456" as it is, but by specifying BitDataEnd Lsb instead, we would obtain "5634", since the input is interpreted as "0x78563412".
ExtractBitField 0008 16 Unpack|BinToAscii 0
- Frame value: 0x1B14
|SrcFieldStartBit||Integer (16 bits)||Specifies the first bit (beginning with 0) to be taken from the phase 1 data. This is not necessarily a multiple of eight! Please note that 0 always corresponds to bit 0 of the first byte (no matter if LSB or MSB encoding is used).|
|SrcFieldBits||Integer (8 bits)||
Specifies the number of bits to be taken from the phase 1 data. This is not necessarily a multiple of eight!
If this value is 0, all data from SrcFieldStartBit to the end of the phase 1 template is taken.
|Filter||Bit mask (8 bits)||
Specifies the conversion rules for the data
extracted from phase 1. Please note that this
filter shall return an ASCII number by convention.
For every of these filter bits, a specific data conversion mechanism is specified. This mechanism is applied to a TemplateCommand if the filterbit is set.
The activated filters are applied ordered by there value. Starting with the smallest value.
|BcdToBin||Boolean (bit 0x80)||
Converts a BCD Number (must only contain nibbles 0-9, not A-F) to a binary number. Input and Output data are MSB encoded.
The length of the destination data is the length of the source data (in bytes) multiplied by 0.83048 (and rounded down to the next byte boundary).
Some source data's binary representation is longer than the calculated destination length. If such source data could occur, an additional leading zerobyte has to be inserted in front of the source data
|BinToAscii||Boolean (bit 0x40)||
Convert Binarydata to ASCII by converting the ASCII
characters 0x00-0x09 to 0x30-0x39 and 0x0A-0x0F to
|Unpack||Boolean (bit 0x20)||
Splits the high and the low nibble of each byte
into two separate bytes, where the high nibble is
set to 0.
|BinToBcd||Boolean (bit 0x10)||
Converts a binary Number to a BCD encoded number. Input and Output data are MSB encoded.
The length of the destination data is the length of the source data in bytes) multiplied by 1.2041 (and rounded up to the next byte boundary).
This is not exactly the inverse of BcdToBin, since the length may differ.
|SwapNibbles||Boolean (bit 0x08)||
Swap the higher nibble (bits 5-7) of each byte with
the lower nibble (bits 0-3).
|Pack||Boolean (bit 0x04)||
Merges two Bytes at a time to a single one by
removing the leading nibble (which has to be 0) of
|AsciiToBin||Boolean (bit 0x02)||
Convert ASCII to Binarydata by converting the ASCII
characters 0x30-0x39 to 0x00-0x09 and 0x41-0x49
(0x61-0x66) to 0x0A-0x0F.
|Reverse||Boolean (bit 0x01)||
Swap the first byte with the last one, the second
one with the next to last one and so on.
|DstFieldBytes||Integer (8 bits)||
Specifies the actual number of bytes of phase 2. If Filter returns ASCII formatted data, this value corresponds to the number of digits.
If this value is 0, it is automaticially set to the length of the SrcFieldBits, rounded up to a multiple of 8 and adapted to the converted format by Filter.
If this value is greater than SrcFieldBits , the most significant digits will be filled with zeros.
If this value is smaller than SrcFieldBits , the most significant digits will be removed.