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

¾Ö¾

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

¾¾¾¾¾

Ö

DEC [m]

Decrement data memory

Description

Data in the specified data memory is decremented by 1.

Operation

[m]

¬ [m]-1

Affected flag(s)

TO

PDF

OV

Z

AC

C

¾

¾

¾Ö¾

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

¾Ö¾

¾

HT48R062/HT48C062

Rev. 1.11

17

October 30, 2006