HT46R47
CPLA [m]
Complement data memory and place result in the accumulator.
Description
Each bit of the specified data memory is logically complemented (1's comple-
ment). Bits which previously contained a 1 are changed to 0 and vice-versa.
The complemented result is stored in the accumulator and the contents of
the data memory remain unchanged.
Operation
ACC ¬ [m]
Affected flag(s)
TC2 TC1 TO PD OV
Z
AC
C
¾
¾
¾
¾
¾
Ö
¾
¾
DAA [m]
Decimal-Adjust accumulator for addition.
Description
The accumulator value is adjusted to the BCD (Binary Coded Decimal) code.
The accumulator is divided into two nibbles. Each nibble is adjusted to the
BCD code and an internal carry (AC1) will be done if the low nibble of the ac-
cumulator is greater than 9. The BCD adjustment is done by adding 6 to the
original value if the original value is greater than 9 or a carry (AC or C) is set;
otherwise the original value remains unchanged. The result is stored in the
data memory and only the carry flag (C) may be affected.
Operation
If ACC.3~ACC.0 >9 or AC=1
then [m].3~[m].0 ¬ (ACC.3~ACC.0)+6, AC1=AC
else [m].3~[m].0) ¬ (ACC.3~ACC.0), AC1=0
and
If ACC.7~ACC.4+AC1 >9 or C=1
then [m].7~[m].4 ¬ ACC.7~ACC.4+6+AC1,C=1
else [m].7~[m].4 ¬ ACC.7~ACC.4+AC1,C=C
Affected flag(s)
TC2 TC1 TO PD OV
Z
AC
C
¾
¾
¾
¾
¾
¾
¾
Ö
DEC [m]
Decrement data memory.
Description
Operation
Data in the specified data memory is decremented by 1.
[m] ¬ [m]-1
Affected flag(s)
TC2 TC1 TO PD OV
Z
AC
C
¾
¾
¾
¾
¾
Ö
¾
¾
Rev. 1.40
32
July 18, 2001