Should write at the onchip extram address of 0x2a0 but writes at 0x0a0 according to data sheet page 30, will check for RD2 tomorrow if it functions same way
1) P2 is not in use/affected by access to ERAM, it would upset the use of P2 as a GP port if it did, you must use MOVX @dptr.
2) same for RD2

Erik