Binary coded decimal: Difference between revisions
→{{header|PL/M}}: Added simple example that is as per the task.
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=={{header|PL/M}}==
{{works with|8080 PL/M Compiler}} ... under CP/M (or an emulator)
The 8080 PL/M compiler supports packed BCD by wrapping the 8080/Z80 DAA instruction
This is basically {{Trans|Z80_Assembly}}
<lang pli>100H: /* DEMONSTRATE PL/M'S BCD HANDLING */
BDOS: PROCEDURE( FN, ARG ); /* CP/M BDOS SYSTEM CALL */
DECLARE FN BYTE, ARG ADDRESS;
GOTO 5;
END BDOS;
PR$CHAR: PROCEDURE( C ); DECLARE C BYTE; CALL BDOS( 2, C ); END;
PR$NL: PROCEDURE; CALL PR$CHAR( 0DH ); CALL PR$CHAR( 0AH ); END;
PR$BCD: PROCEDURE( V ); /* PRINT A 2-DIGIT BCD NUMBER */
DECLARE V BYTE;
DECLARE D BYTE;
D = SHR( V AND 0F0H, 4 );
CALL PR$CHAR( D + '0' );
D = V AND 0FH;
CALL PR$CHAR( D + '0' );
END PR$BCD ;
DECLARE ( A, B, I ) BYTE;
A = SHL( 1, 4 ); /* WORKS AROUND A POSSIBLE BUG IN THE 8080 EMULATOR */
/* OR MY UNDERSTANDING OF THE DEC() FUNCTION... */
A = 19H;
CALL PR$BCD( DEC( A + 1 ) ); CALL PR$NL;
A = 30H;
CALL PR$BCD( DEC( A - 1 ) ); CALL PR$NL;
B = 00H;
A = 99H;
A = DEC( A + 1 ); /* ADD 1 TO 99 - THIS WILL SET CARRY */
B = DEC( B PLUS 0 ); /* ADD THE CARRY TO GET THE LEADING DIGITS */
CALL PR$BCD( B ); CALL PR$BCD( A ); CALL PR$NL;
EOF</lang>
{{out}}
<pre>
20
29
0100
</pre>
A more complex example, showing how the DEC function can be used to perform unsigned BCD addition and subtraction on arbitrary length BCD numbers.
<lang pli>100H: /* DEMONSTRATE PL/M'S BCD HANDLING */
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