BillyBoyo wrote:... I was wondering what the point of the wrap was...
I agree, I don't understand what the point of storage "wrapping" is, too.
At one point setting bits in the high order byte of the even register is meaningless, since they would not be used for addressing in the 24-bit addressing mode. On the other hand, if a programmer is going to turn around and use the register one would be better off if the register is correct. I will often use regs 14 and 15 to build a message from message segments, finishing up with code like this to build an RDW -
... Code to build the message, bumping reg 14 as it goes
Now this scheme won't work if reg 14 wrapped, but you'll never encounter this in the real world, so who cares.