HT46R51/HT46R52
CPLA [m]
Complement data memory and place result in the accumulator
Description
Each bit of the specified data memory is logically complemented (1¢s complement). 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)
TO
PDF
OV
Z
AC
C
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 accumu-
lator 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 accumulator is greater than 9. The BCD ad-
justment 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)
TO
PDF
OV
Z
AC
C
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)
TO
PDF
OV
Z
AC
C
¾
¾
¾
Ö
¾
¾
DECA [m]
Decrement data memory and place result in the accumulator
Description
Data in the specified data memory is decremented by 1, leaving the result in the accumula-
tor. The contents of the data memory remain unchanged.
Operation
ACC ¬ [m]-1
Affected flag(s)
TO
PDF
OV
Z
AC
C
¾
¾
¾
Ö
¾
¾
Rev. 1.40
27
July 12, 2005
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
