OCTAL
"Loading +CAPS" $PRINT CRLF
; Hijacking Streams - this example inserts a code-path into
; both the user and console IO streams
; Received input is stripped to 7 bits and converted to uppercase
CREATE +CAPS
       LDA ZCHIN                get console in vector
       CPA ACCCIN               already installed?
       JMP END                  yes - exit
       STA CCIN                 save to chain console in
       LDA ACCCIN               get address of chain console code in
       STA ZCHIN                set console in vector
       STA ZIN                  also to general in
       JMP END                  exit, vectors set
CCIN   OCT 0                    prev ZCIN
ACCCIN DEF CCCIN                address of chain console code in
* constants and variables...
LC127  DEC 127                  7-bit mask
C32645 DEC 32645                constants for input filter code
C32671 DEC 32671
LCM32  DEC -32
* new console in handler sub...
CCCIN  NOP
       JSB CCIN,I               call original console in sub
* input filter code
       AND LC127                mask to 7-bit
       STA 1                    save to B
       ADA C32645
       SSA                      greater than "z"?
       JMP NIF                  yes - no convert
       LDA 1
       ADA C32671
       SSA,RSS                  less than "a"?
       JMP NIF                  yes - no convert
       LDA 1
       ADA LCM32                convert to uppercase if lowercase
       RSS                      skip to return
NIF    LDA 1                    restore char
* end input filter code       
       JMP CCCIN,I              return
* end of +CAPS
END
;
"Loading -CAPS" $PRINT CRLF
; restores previous console and general IO vectors
CREATE -CAPS /KEEP
       LDA CCIN
       SZA,RSS
       JMP END
       STA ZCHIN
       STA ZIN
END
;
CONSOLE