When eliminating unprintability, I have often used a table something like the
following:
TABLE DC 256C' ' (X'40', or the blank character; this is the default
that I want printed if an unprintable is found; it could also be X'FF')
ORG TABLE+C'0'
DC C'0123456789' These are all the
printable numbers.
ORG TABLE+C'A'
DC C'ABCDEFGHI' Upper case English
alphabet letters A through I
ORG TABLE+C'a'
DC C'abcdefghi' Lower case English
alphabet letters a through i
ORG TABLE+C'$'
DC C'$' U.S.
Dollar sign character
etc.
etc.
ORG , Don't forget
to put one of these at the end.
The nice thing about this kind of table is that you don't have to know exactly
where in the 256-byte array of printable characters any given character is
defined.
But you do need to know that all 10 numbers are contiguous, than only letters
A-I are contiguous (in EBCDIC), that there is a gap, then the letters J-R are
contiguous, etc. You could even program around that by turning the ORG and DC
into a macro that only defines one character per invocation.
E.g.: DEFINE MACRO &BYTE
ORG TABLE+C'&BYTE'
DC C'&BYTE'
MEND
TABLE DC 256C' '
DEFINE A
DEFINE B
DEFINE $
etc.
etc.
ORG , Don't forget to put
one of these at the end. Or you could add this into the macro and then you
don't have to remember.
Bill Fairchild
