unsigned char rather than char for values that end up passed to
isascii() and also used as array indices.
Patch submitted by Joseph Myers <jsm28@cam.ac.uk> in PR 8093.
I found an error in the table. The same error is found in the SUNOS
4.1.1 version of bcd. It has apparently been around a long time.
The error caused 'Q' and 'R' to have the same punch code. I only
noticed the error due to someone pointing t out to me when the
program was used to print a cover for an APA!