Fill Direct enables you to set a range of numeric operands or MBs. The function copies a value from a desired operand, then writes that value into every operand within in the set range.
Operand A: this is the operand which contains the value to be copied.
Operand B: this is the first operand in the range.
Operand C: this sets the length, meaning the number, of operands in that range.