I want to refer to hex values of a packed decimal field in COBOL?

Answer 1

Redefine the field as a pic x(n) field.
Where n is the number of digits in the packed field plus 1 divided by 2.
This is assuming that the number of digits in the packed field in odd. If the number is even then you are stupid and add 2!!

Answer 2

01 binary-number s9(4) comp value 15. 01 text-binary-number redefines binary-number. 03 filler pic x. 03 test-unsigned-value pic x. 01 packed-number s9(3) comp-3. 01 text-packed-number redefines packed-number. 03 filler pic x. 03 packed-sign pic x. procedure division. if test-unsigned-value and packed-sign equals test-unsigned-value then ... end-if. That should work for unsigned values. set the binary value to 13 for negative and 12 for positive. And don't forget to close your previous questions and allocate 10 points!!!