I conected the SRAM, it's a HM6264 (8Kx8) and the latch (74373),
the pins PSEM and RD are conected into an positive AND gate to make the mcu capable of execute program data stored into te external RAM, the pin EA are conected at Vcc.

But the problem is (using LEDs to see the state of the ports P0 and P2) these two ports become at high level all the time.
Replacing the comands "MOVX @DPTR" by "MOV P1" the program function properly but the data are send to port P1 instead of the external RAM.