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Semiconductor Group
154
Instruction Set
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
A, #99H
DA
A
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.
Operation:
DA
contents of accumulator are BCD
if [[(A3-0) > 9]
∨
[(AC) = 1]]
then (A3-0)
←
(A3-0) + 6
and
if [[(A7-4) > 9]
∨
[(C) = 1]]
then (A7-4)
←
(A7-4) + 6
Bytes:
1
Cycles:
1
Encoding:
1 1 0 1
0 1 0 0
*
Summary of Contents for SAB 80515 Series
Page 9: ...Semiconductor Group 9 Introduction Figure 1 2 Block Diagram ...
Page 12: ...Semiconductor Group 12 Fundamental Structure Figure 2 1 Detailed Block Diagram ...
Page 18: ...Semiconductor Group 18 Central Processing Unit Figure 3 1 Fetch Execute Sequence ...
Page 73: ...Semiconductor Group 73 On Chip Peripheral Components Figure 7 25 A D Converter Block Diagram ...
Page 83: ...Semiconductor Group 83 On Chip Peripheral Components Figure 7 33 a Timer 2 Block Diagram ...
Page 215: ...Device Specifications Semiconductor Group 215 ...
Page 217: ...Device Specifications Semiconductor Group 217 Pin Configuration P LCC 68 ...
Page 219: ...Device Specifications Semiconductor Group 219 Logic Symbol ...
Page 226: ...Device Specifications Semiconductor Group 226 Figure 1 Block Diagram ...
Page 229: ...Device Specifications Semiconductor Group 229 Figure 2 Memory Address Spaces ...
Page 239: ...Device Specifications Semiconductor Group 239 Figure 4 Block Diagram of the A D Converter ...
Page 241: ...Device Specifications Semiconductor Group 241 Figure 5 Interrupt Request Sources ...
Page 242: ...Device Specifications Semiconductor Group 242 Figure 6 Interrupt Priority Level Structure ...