...And trying Al's suggestion of removing the DEC modifier (only on receiver side and for both hserin and hserout)
Dennis, I suggested you to remove the DEC modifier in Transmitter not in the receiver side.

The reason is that you Tx a pure ascii code and convert it to decimal at the receiver side, while now you are modifying the byte twice (at Tx & at Rx) and can yield wierd results.

Al.