HP 3000 Manuals HP 3000 Manuals
SPL BEXTRACT Procedure: Bit Extraction
<< BEXTRACT SPL BIT EXTRACTION >>
<< >>
<< This procedure emulates the SPL bit extraction, for example: >>
<< x := y.(10:4); >>
<< as an SPL procedure: >>
<< x := BEXTRACT(y,10,4); >>
<< >>
<< The parameters to BEXTRACT are: >>
<< wd -- Word (unsigned short) to extract bits from. >>
<< sb -- Starting bit of field (0 through 15, left to right).>>
<< nb -- Number of bits in field. >>
<< >>
<< The return value will be the extracted field, right justified >>
<< in a 16 bit (unsigned short) word. >>
LOGICAL PROCEDURE BEXTRACT(wd,sb,n);
VALUE wd, sb, nb;
LOGICAL wd;
INTEGER sb, nb;
BEGIN
BEXTRACT := (wd & LSL(sb)) & LSR(16-nb);
END;