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Siemens SINUMERIK Controller
Servo/Axis · Basic · 10-20 minutes
Siemens 840D 12720 - Channel block program number for macro call (G65/G66) missing
During macro call with G65/G66 no program number was defined. The program number must be programmed with address "P".
12720
Siemens 840D 12720 - Channel block program number for macro call (G65/G66) missing
Channel block program number for macro call (G65/G66) missing
During macro call with G65/G66 no program number was defined. The program number must be programmed with address "P".
Safety
- Refer to Siemens documentation
- Ensure qualified technician performs repairs
Common Causes
- G65 or G66 command issued without P address parameter specifying the macro program number
- P parameter omitted or deleted during program editing
- Incorrect syntax in macro call block - P value not properly formatted as numeric
- Program loaded from external source with incomplete macro call syntax
- CNC operator manually entered G65/G66 without required P parameter in MDI mode
Troubleshooting Steps
- 1Review the program at the indicated block number and verify G65 or G66 command contains P address with valid program number (e.g., G65 P1234)
- 2Check program source files and CAM post-processor output to confirm macro calls are generated with P parameter syntax
- 3Verify the referenced macro program number exists in the CNC memory or external program storage
- 4Edit the program block to add or correct the P parameter with appropriate program number and retest
- 5Clear the alarm, reload the corrected program, and execute single block to confirm macro call processes without error
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