F128_DRCL

The function rotates the value at output d via the carry flag to the left. The number of bits at output d to be rotated to the left is specified by the value assigned at input n. This shift can lie between 0 and 255 (only the lower value byte of n is effective).

Parameters

Input

n (INT)

Number of bits to be rotated (range: 0 to 255)

Output

d (DWORD, DINT, UDINT, DATE, TOD, DT)

32-bit area

Remarks

• The bit value at bit position 32 - n is stored in the carry flag. The function shifts out n bits to the left via bit 31 (MSB), and then along with the inverted carry flag first, continues via bit 0 (LSB) into the storage range. Position n - 1 now has the inverted value of the carry flag.

• When input n = 0, no rotation occurs and the carry flag remains unchanged.

• When at input n > 32, the same result is achieved as with a number n < 32: e.g. n = 33 produces the same result as when n = 0; n = 34 the same as n = 1.

Error flags

sys_bIsCarry (turns to TRUE for one scan)

if the bit at position 32 - n has the value 1.