359
3. Instructions
CS/CJ/NSJ Series Instructions Reference Manual (W474)
Symbol Math Instructions
3
–/–L
Flags
Function
z –
–(400) subtracts the binary values in Su from Mi and outputs the result to R. When the result is
negative, it is output to R as a 2's complement.
z –L
–L(411) subtracts the binary values in Su and Su+1 from Mi and Mi+1 and outputs the result to R, R+1.
When the result is negative, it is output to R and R+1 as a 2's complement.
Name Label
Operation
– –L
Error Flag ER OFF OFF
Equals Flag = • ON when the result is 0.
• OFF in all other cases.
• ON when the result is 0.
• OFF in all other cases.
Carry Flag CY • ON when the subtraction results in a borrow.
• OFF in all other cases.
• ON when the subtraction results in a borrow.
• OFF in all other cases.
Overflow Flag OF • ON when the result of subtracting a negative num-
ber from a positive number is in the range 8000 to
FFFF hex.
• OFF in all other cases.
• ON when the result of subtracting a negative num-
ber from a positive number is in the range
80000000 to FFFFFFFF hex.
• OFF in all other cases.
Underflow Flag UF • ON when the result of subtracting a negative num-
ber from a positive number is in the range 0000 to
7FFF hex.
• OFF in all other cases.
• ON when the result of subtracting a positive num-
ber from a negative number is in the range
00000000 to 7FFFFFFF hex.
• OFF in all other cases.
Negative Flag N • ON when the leftmost bit of the result is 1.
• OFF in all other cases.
• ON when the leftmost bit of the result is 1.
• OFF in all other cases.
−
R CY
Mi
Su
(Signed binary)
(Signed binary)
(Signed binary)
CY will turn ON
when there is a
borrow.
−
Su+1
CY
R
Mi+1
R+1
Mi
Su
(Signed binary)
(Signed binary)
(Signed binary)
CY will turn ON
when there is a
borrow.