Module: Ansible::KNX::ScalarValue

Included in:
DPT5
Defined in:
lib/ansible/knx/knx_dpt_scalar.rb

Overview

KNX specification declares some special DPTs (5.001 and 5.003) that need scalar adjustment functions to get the true value contained in a DPT frame.

Instance Method Summary collapse

Instance Method Details

#from_scalar(val, data_range, scalar_range) ⇒ Object

convert value from its scalar representation e.g. in DPT5.001, 50(%) => 0x7F , 100(%) => 0xFF



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# File 'lib/ansible/knx/knx_dpt_scalar.rb', line 47

def from_scalar(val, data_range, scalar_range)
    if data_range.is_a?(Range) and scalar_range.is_a?(Range) then
        a = (scalar_range.max - scalar_range.min).to_f / (data_range.max - data_range.min)
        b = (scalar_range.min - data_range.min)
        #puts "a=#{a} b=#{b}"
        return ((val - b) / a).round
    else
        return val
    end
end

#to_scalar(val, data_range, scalar_range) ⇒ Object

convert value to its scalar representation e.g. in DPT5.001, 0x7F => 50(%), 0xFF => 100(%)



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# File 'lib/ansible/knx/knx_dpt_scalar.rb', line 35

def to_scalar(val, data_range, scalar_range)
    if data_range.is_a?(Range) and scalar_range.is_a?(Range) then   
        a = (scalar_range.max - scalar_range.min).to_f / (data_range.max - data_range.min)
        b = (scalar_range.min - data_range.min)
        return (a*val + b).round
    else
        return val
    end
end