Siemens SINUMERIK 840D sl Function Manual page 590

Detailed description
2.4 Program test
Single-block type
The following different types of single block are provided:
• Decoding single block
• Action single block
Action single block is the initial setting.
For selecting the single block operation, see:
References:
/BEM/ Operator's Guide HMI Embedded
Caution
In a series of G33/G34/G35 blocks, a single block is only operative if "dry run feed" is
selected.
Calculation blocks are not processed in single step mode (only if single decoding block is
active).
SBL2 is also ineffective with G33/G34/G35.
Selection of single block type
An operator input in the Program control area on the HMI specifies the single block type.
Activation
On detection of the "Single Block" key on the machine control panel, the basic PLC program
sets interface signal:
DB21, ... DBX0.4
to activate the single block function.
If there is no machine control panel available, HMI Embedded can be used to activate the
"Single block" key in the machine area with the same result.
In the case of HMI Advanced without machine control panel, a user display must be
configured with a suitable softkey that sets/resets interface signal:
DB21, ... DBX0.4.
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With this type of single block, all blocks of the part program (even the pure computation
blocks without traversing motions) are processed sequentially by "NC Start".
With this type of single block, all blocks that initiate actions (traversing motions, auxiliary
function outputs, etc.) are processed individually. Blocks that were generated additionally
during decoding (e.g., for cutter radius compensation at acute angles) are also processed
individually in singleblock mode. Processing is however not stopped at calculation blocks
as these do not trigger actions.
Basic logic functions: Mode group, channel, program operation, reset response (K1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0