MODBUS: use slider to control temperature and how to set a bit into a word

Configuration
1

Hi all,
to control my climate system i need via modbus to do 2 things:

  1. I need to set a register to set temperature, Is it possible to use a slider or an input box to set the temperature and send it via modbus?

  2. To power on or of the controller i need to set a bit into a word register, how i can do it?

The needs is to set the second bit to 0 or 1 due:
1st bit enable or disable the manual use of controller
2nd bit power on or off the controller
3rd bit set winter/summer
4rd bit set manual/automatic fan

Thanks

2

hints? I try to find some ways but i haven’t ideas