Sets the BigNum modulo divisor
D OP_SETBMD => ?
OP_SETBMD is defined as the single byte 0xeb.
This instruction sets the BigNum modulo to the top element on the stack (D). The script fails if D is not a BigNum or a little-endian sign-magnitude encoded integer that is greater than 0 and less than or equal to 2^4096 (R.O1). Note that this limit is one larger than the largest possible BigNum, but can be pushed onto the stack as data in little-endian sign-magnitude encoded integer format.
Efficient implementations may want to internally use 0 to denote a BMD of 2^4096.