Reading Mahmoods entry, I just realize: this is not a 8052 question, no processor involved, YES, gang a 232 and a 1490, that's all.

If, however you need RS485 support, it is a totally different store although the driver chips are the same.

IF you do not need galvanic isolation, the 75176 type chips are A LOT cheaper 422 drivers that tha max1490.

Erik