User manual

36
CHAPTER 11
CATC Scripting Language for USB Primitives
result = C # The result is given in
hexadecimal. The result in binary is 1100.
In the call to GetNBits: starting at bit 2, reads 4 bits (1100), and returns the value
0xC.
NextNBits()
NextNBits (<bit_count integer>)
Return value
None.
Comments
Reads bit_count bits from the data source specified in the last call to
GetNBits, starting after the last bit that the previous call to GetNBits or
NextNBits returned. If called without a previous call to GetNBits, the result is
undefined. Note that bits are indexed starting at bit 0.
Example
raw = 'F0F0';# 1111000011110000 binary
result1 = GetNBits ( raw, 2, 4 );
result2 = NextNBits(5);
result3 = NextNBits(2);
Trace ( "result1 = ", result1, " result2 = ", result2,
" result3 = ", result3 );
This will generate this trace output:
result1 = C result2 = 7 result3 = 2
In the call to GetNBits: starting at bit 2, reads 4 bits (1100), and returns the value
0xC.
In the first call to NextNBits: starting at bit 6, reads 5 bits (00111), and returns
the value 0x7.
In the second call to NextNBits:startingatbit11(=6+5),reads2bits(10),
and returns the value 0x2.
Parameter Meaning Default Value Comments
bit_count integer