HEIDENHAIN TNC 620 User Manual page 326

9
Programming Q parameters
9.1 Principle and overview of functions
Programming notes
You can mix Q parameters and numerical values within an
NC program.
Q parameters can be assigned numerical values between
-999,999,999 and +999,999,999. The input range is limited to
16 digits, of which 9 may be before the decimal point. Internally the
TNC calculates numbers up to a value of 10
You can assign a maximum of 255 characters to QSQS parameters.
The TNC automatically assigns some Q and QS
parameters the same data, e.g. the Q parameter
Q108 is automatically assigned the current tool
radius.
Further Information:
page 373
The TNC saves numerical values internally in a binary
number format (standard IEEE 754). Due to this
standardized format some decimal numbers do
not have an exact binary representation (round-off
error). Keep this in mind especially when you use
calculated Q-parameter contents for jump commands
or positioning movements.
326
10 .
" Preassigned Q parameters",
HEIDENHAIN | TNC 620 | ISO Programming User's Manual | 9/2016