Description:

Pop the top short off of the stack and subtract it from the new top short on the stack.

Pseudo Code:

shortVal = stack[sp - 2]
sp = sp - 2
stack[sp - 2] = stack[sp - 2] - shortVal
pc = pc + 1

Flags Affected:

D	H	C	Z	N

Possible Errors:

tvmStackUnderflow

-

There were not enough shorts in the stack.

Example:

subs

Before stack   top 1 0x0B 2 0x17 3 0xAA 4 0x32   bottom

After stack   top 1 0x9F 2 0x1B   bottom