how to design temperature and humidity sensor with rs485 output

Hi Josh Wyatt 

thanks for the answer, you know that RS485 has a multiple register operation like holding registers,  write registers, and read registers and every register have multiple registers for reading/write the value, here my doubt is how can i create those registers and how can i store the data to that output registers.

regards

surya

Hi Josh Wyatt 

thanks for the reply, yes you had already shared the reference designs but that design shows the value or string transmitted continuously so other end pc or MC receive the string/value with the help of rs485 to usb/rs232 converter but i am asking about my microcontroller transmit the data like i2c sensor, Currently, i have an ultrasonic level sensor with RS485 output that manufacture attached the datasheet of the sensor the datasheet have an only one page data like  

device id(1), holding register value(03), level registers like data is 4byte length so register value is 100 to 103 that's all so i connect the level sensor with rs485 to ttl out (max485 ic based) converter to my controller and send the request like

char buf[]={0x01,0x03,0x64,0x04,0x52,0x34};//don't mind CRC value it's just example

serial.write(buf,8);

then my controller serial receive 10byte of data including deviceid, level,readed data length,CRC

i want to do the same with my controller, my controller replies to PC/mc when PC/controller sends the data request as per the above example format.