Modbus Interface

Hello fellas,

I am currently working on a MOODBUS protocol with UART interface to collect data from the slave device which is a sensor and send the data to Gateway master node.

UART interface: RS485 brakout board: Sparkfun, 8051 Micro-controller(ANU23600 1715G) by amicom.

I am new to the embedded programming and I currently have a two versions of customized code written in C per the project

Version:1: where the slave node is communicating to the gateway node (master) but not producing output, in the output I've connected the oscilloscope where I'm not getting any data output. I couldn't able to figure out why the slave node is not working.

The baud rate as 9600 bps. 

Version:2: The slave is giving the output but not communicating to the gateway. 

Could you guys please let me how to debug the program and make it work ?

Thanks in advance!