Reading 8 coil points as a 1 byte in Modbus

[savaskorkmaz]

Hi I got an error when i use this script in log screen.
* table:[2] * string: broadcast read not allowed

What could be the reason ?

It's not possible to do this via a profile, you will have to use scripts. You can access the same RS485 port from both profiles and scripts using mbproxy.

You can read multiple coils/inputs via a script and convert to a number.

Code:

function bitstonumber(bits)
  local res = 0

  for bnum, bval in ipairs(bits) do
    if bval then
      res = bit.bor(res, bit.lshift(1, bnum - 1))
    end
  end

  return res
end

mb = require('mbproxy').new()
mb:setslave(1)

bits = { mb:readcoils(8, 8) }
if #bits == 8 then
  mode = bitstonumber(bits)
  log(mode)
else
  log(bits)
end

The addressing probably starts from 0 so you have to subtract 1 from the documented addresses.
Temperature will not work with "value_multiplier": 0.1, try using "datatype": "float16" and "bus_datatype": "float16" without "value_multiplier".