
INSTRUCTION SET
S3C8248/C8245/P8245/C8247/C8249/P8249
6-14
ADC
— Add with carry
ADC
dst,src
Operation:
dst
←
dst + src + c
The source operand, along with the setting of the carry flag, is added to the destination operand
and the sum is stored in the destination. The contents of the source are unaffected. Two's-
complement addition is performed. In multiple precision arithmetic, this instruction permits the
carry from the addition of low-order operands to be carried into the addition of high-order
operands.
Flags:
C:
Set if there is a carry from the most significant bit of the result; cleared otherwise.
Z:
Set if the result is "0"; cleared otherwise.
S:
Set if the result is negative; cleared otherwise.
V:
Set if arithmetic overflow occurs, that is, if both operands are of the same sign and the result
is of the opposite sign; cleared otherwise.
D:
Always cleared to "0".
H:
Set if there is a carry from the most significant bit of the low-order four bits of the result;
cleared otherwise.
Format:
Bytes
Cycles
Opcode
(Hex)
Addr Mode
dst src
opc
dst | src
2
4
12
r
r
6
13
r
lr
opc
src
dst
3
6
14
R
R
6
15
R
IR
opc
dst
src
3
6
16
R
IM
Examples:
Given: R1 = 10H, R2 = 03H, C flag = "1", register 01H = 20H, register 02H = 03H, and
register 03H = 0AH:
ADC
R1,R2
→
R1 = 14H, R2 = 03H
ADC
R1,@R2
→
R1 = 1BH, R2 = 03H
ADC
01H,02H
→
Register 01H = 24H, register 02H = 03H
ADC
01H,@02H
→
Register 01H = 2BH, register 02H = 03H
ADC
01H,#11H
→
Register 01H = 32H
In the first example, destination register R1 contains the value 10H, the carry flag is set to "1",
and the source working register R2 contains the value 03H. The statement "ADC R1,R2" adds
03H and the carry flag value ("1") to the destination value 10H, leaving 14H in register R1.
Summary of Contents for C8245
Page 31: ...ADDRESS SPACES S3C8248 C8245 P8245 C8247 C8249 P8249 2 20 NOTES ...
Page 107: ...INTERRUPT STRUCTURE S3C8248 C8245 P8245 C8247 C8249 P8249 5 18 NOTES ...
Page 195: ...INSTRUCTION SET S3C8248 C8245 P8245 C8247 C8249 P8249 6 88 NOTES ...
Page 221: ...I O PORTS S3C8248 C8245 P8245 C8247 C8249 P8249 9 16 NOTES ...
Page 245: ...16 BIT TIMER 0 1 S3C8248 C8245 P8245 C8247 C8249 P8249 12 10 NOTES ...
Page 249: ...WATCH TIMER S3C8248 C8245 P8245 C8247 C8249 P8249 13 4 NOTES ...
Page 267: ...A D CONVERTER S3C8248 C8245 P8245 C8247 C8249 P8249 15 6 NOTES ...
Page 299: ...S3P8245 P8249 OTP S3C8248 C8245 P8245 C8247 C8249 P8249 21 8 NOTES ...
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