Measurement Computing DBK70 - Manual (Page 54)

5-24 919092 PidPRO & PidPRO+
Raw -> Units Conversion Method
Once the binary data of a specified message has been captured, the DBK70 converts it to user units, for
example: RPM, temperature, percent load, or pressure. This unit conversion occurs before the data is
displayed in the PidPRO interface or supplied on the DBK70’s serial port for other programs.
PidPRO provides 3 different methods for specifying the conversion information. These are:
o Units/Bit (Units per bit)
o Min/Max (2-point)
o Binary Point
The different methods are supplied to accommodate the different ways in which ECM and vehicle
manufacturers state scaling information.
Units/Bit essentially specifies the resolution of the binary data relative to the user units. For example, if
the binary data is being converted to temperature, a Units/Bit value of 1 means that one binary count in the
raw data equals one degree of temperature. A Units/Bit value of 0.1 means that one binary count in the
raw data equals one tenth of a degree and 10 counts equals 1 degree. When using this method, the
Units/Bit and the User Units Low Limit fields are used to specify the conversion parameters. The User
Units High Limit is disabled, but the value is shown as an informational aid.
In the example below, a data length of 8 bits and a data format of unsigned produces a span of 0 to 255 in
the raw incoming data. A Units/Bit value of 0.7843 provides a span of 200 units and a Low Limit of -100
provides an offset so that the limits of the user units [relative to the limits of the incoming data] is -100 to
+100.
If the User Units Low Limit is changed to 0, the transfer function will be shifted so that the user units
limits will be 0 to +200.