ht827a0 Holtek Semiconductor Inc., ht827a0 Datasheet - Page 35

• Manufacturer Part Number: ht827a0
• Description: 8-bit Microcontroller With Voice Rom
• Manufacturer: Holtek Semiconductor Inc.

CPLA [m]
Description
Operation
Affected flag(s)
DAA [m]
Description
Operation
Affected flag(s)
DEC [m]
Description
Operation
Affected flag(s)
Complement data memory place result in the accumulator
Each bit of the specified data memory is logically complemented (1¢s comple-
ment). Bits which previously contained a one are changed to zero and
vice-versa. The complemented result is stored in the accumulator and the
contents of the data memory remain unchanged.
ACC ¬ [m]
Decimal-Adjust accumulator for addition
The value of the accumulator is adjusted to a BCD (Binary Code Decimal)
code. If bits 0~3 of the accumulator are greater than 9 or AC is one, six is
added to the low-order nibble of the accumulator, deriving a BCD digit in the
low-order nibble. Similarly, if bits 4~7 of the accumulator are greater than
nine or C is one, six is added to the high-order nibble of the accumulator, gen-
erating a BCD digit in the high-order nibble. The result is stored in the data
memory.
If ACC.3~ACC.0 >9 or AC=1
then ([m].3~[m].0) ¬ (ACC.3~ACC.0)+6
else ([m].3~[m].0) ¬ (ACC.3~ACC.0)
and
If ACC.7~ACC.4 >9 or C=1
then ([m].7~[m].4) ¬ (ACC.7~ACC.4)+6,C=1
else ([m].7~[m].4) ¬ (ACC.7~ACC.4),C=C
Decrement data memory
Data in the specified data memory are decremented by one.
[m] ¬ [m]-1
TC2
TC2
TC2
¾
¾
¾
TC1
TC1
TC1
¾
¾
¾
TO
TO
TO
¾
¾
¾
PD
PD
PD
¾
¾
¾
35
OV
OV
OV
¾
¾
¾
¾
Z
Z
Z
Ö
Ö
AC
AC
AC
¾
¾
¾
¾
¾
C
C
C
Ö
March 15, 2000
HT827A0