gc80c520a CORERIVER Semiconductor, gc80c520a Datasheet - Page 107

• Manufacturer Part Number: gc80c520a
• Description: Midas1.0 Family Mask Rom/eprom/romless 8-bit Turbo Microcontrollers
• Manufacturer: CORERIVER Semiconductor

Operation:
Encoding:
MiDAS1.0 Family
Cycles:
Bytes:
BCD variables can be incremented or decremented by adding 01h or 99h. If the
Accumulator initially holds 30h (representing the digits of 30 decimal), then the
instruction sequence,
ADD
DA
will leave the carry set and 29h in the Accumulator, since 30 + 99 = 129. The
low-order byte of the sum can be interpreted to mean 30 – 1 = 29.
1
1
DA
- contents of Accumulator are BCD
IF
IF
1
1
A, #99h
A
{[(A
THEN
{[(A
THEN
0
3-0
7-4
1
) > 9]
) > 9]
(A
AND
(A
0 1 0 0
3-0
7-4
∨
∨
)
)
Page 107 of 187
←
←
[(AC) = 1]}
[(C) = 1]}
(A
(A
3-0
7-4
) + 6
) + 6