Siemens SINUMERIK 840C, Operator'S Manual, Page: 133 / 301

4 Machine 01.99
6FC5198-6AA60-0BP1 © Siemens AG 1999 All Rights Reserved
4-66
SINUMERIK 840C, OEM Version for Windows (BA)
program. See also the machine manufacturer’s documentation.
The currently necessary number of block buffers is displayed. A maximum of
23 block buffers is provided as standard for predecoding.
The maxium number of block buffers can be further restricted.
Application: Fast decoding in single block mode.
4.3.4.2 Single block/decoding single block
The same preconditions apply as described in the previous section.
The SINGLE BLOCK (SBL) function is selected when you press the
appropriate key on the machine control panel.
When the NC START key is pressed, one block is executed.
The SINGLE BLOCK function has no effect on arithmetic blocks. Arithmetic
blocks are part program blocks which perform programmed calculations
without outputting them to the machine or the PLC (R parameter operations).
The signal generated takes effect at the end of the current block. Once you
have activated the SINGLE BLOCK function, the "SBL" display appears in the
status field and the LED for the SINGLE BLOCK key on the machine control
panel lights up.
After executing a block, "Stop single block operation" is displayed.
NC START must be pressed again to continue execution.
Pressing the SINGLE BLOCK key on the machine control panel a second time,
deselects the function.
The table below shows with which blocks the "Decoding single block active"
signal or the "Single block active" signal must be preset if a program is to be
executed block by block.
The decoded single block mode can be activated using the DSB program
modification. In contrast to single block mode (on the machine control panel)
decoding is interrupted after every block. Each block (including calculation
blocks) is decoded individually.
Predec. blocks
maximum
Preconditions
Operating
sequence