ST20-C1 STMICROELECTRONICS [STMicroelectronics], ST20-C1 Datasheet - Page 156

• Manufacturer Part Number: ST20-C1
• Description: Instruction Set Reference Manual
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

subc
Code: 21 F1
Description: Subtract Areg from Breg, unsigned with carry propagation. This
instruction is provided for long arithmetic; address calculations may be performed with
add , sub and adc without affecting the carry flag.
Definition:
Status Register:
Comments:
See also: addc sub
156/205
if ( diff
{
}
else
{
}
Breg
Creg
where
Carry bit is set or cleared.
Secondary instruction.
section 4.4.
Areg
Status
Areg
Status
unsigned
unsigned
0 )
carry
carry
Creg
Areg
diff
– the value of diff is calculated to unlimited precision
Breg
unsigned
diff
clear
diff + 2
set
BitsPerWord
Areg
unsigned
) - Status
subtract with carry
carry