Two input pins on the sp3078e need to go high at the same time when I'm sending bytes. I'm using a single output pin on the EM357 to drive both of them high and low. The EM357 datasheet says the max output current for the pin that I'm using is 4 milli Amp. The max input current on the sp3078e is 1 micro Amp. Do these connections require any series resistance or pull-up/pull-down?
Just tie the direction control pins together and drive them directly. I use 3073 with 3.3V GPIO and a TTL UART and it works great. If you are going a long distance - RS-485 on a twisted pair is good for a thousand meters or more - put a termination resistor at the far end. 220 Ohms is good (opinions vary on termination).