The rason i want to do this, is the following:
I need to decode external memory to single 8 bit outputs (like the 573 octal D latch) and input buffers (like 245). The problem with these is that they have only 1 output enalbe (or latch enable) pin. therefore, if i were to access them as external memory i'd need to add and gates beetween the WR or RD pin (depending were they are latches or buffers) and the corresponding decoder line for every IC. One possible solution i came by is the following: since all devices are input only or output only, i could AND the RW and RD pins and send this output to one of the enables of the decoder (138 in this case). Then, the single 8 ouputs of the decoder could just go directly to the output enable of the corresponding device. The reason i wanted to simply directly join the pins is not to seve some cents, but because single gate chips are difficult to come by over here, and a quad AND gate for the use of only one seems like awful waste of PCB space (which i dont have at the moment). Well, thats the reason. Im gonna try the diode resistor and see how it works.
PS: By the way, can anyone tell me why direclty joining those two pins will burn my microcontroller? arent those outputs supposed to have a "weak" 1 (made with pull ups?)