I've also just started with the LP8. I wasn't too impressed by the Arduino code in their docs so I pretty much started from scratch. The problem I'm running into is that I'm not getting any response from the LP8 ... at all. I've checked out my connections and all seems good. The LP8 RDY pin never goes high. If I force it high and send out a request on ModBus, I get no reply.
//set up serial bus ====
LP8 <- hardware.uartWJ
LP8.configure(9600, 8, PARITY_NONE, 2, TIMING_ENABLED , LP8_answer)
//config pins ====
LP8_rdy <- hardware.pinT
LP8_en <- hardware.pinP
LP8_rset <- hardware.pinS
Turns out that the reset pin is not used by the LP8 and the enable pin is not needed (as per Hugo's comment)
Checked to make sure my the LP8 RxD goes to PinW and TxD to PinJ. The LP8 RDY pin goes to PinT. I used the TIMING_ENABLED in the uart config because imp docs seemed to indicate it was necessary for ModBus.