Description:

Convert the top short on the stack into a byte by chopping off the high byte.  The stack shrinks by one byte and the Carry flag is set if the short value is out of the byte range (like an overflow).

Pseudo Code:

(byte)stack[sp - 2] = byte((short)stack[sp - 2])
sp = sp - 1

Flags Affected:

D	H	C	Z	N

Possible Errors:

tvmStackUnderflow

-

There were not enough bytes on the stack.

Example:

convsb

Before stack   top 1 0xF4 2 0x73   bottom

After stack   top 1 0xF4   bottom