These are arguably the most used parameters in this range. They allow you to map a custom G-code to a specific macro program number.
Before editing any 9900 parameter, follow this checklist:
: Enabling Helical Interpolation (9925.0) or Custom Macro B (9926.7).
Press the SYSTEM key and type 3202 to find the parameter. Change Bit 4: Change the 4th bit of Parameter 3202 to
: Before changing a single bit, perform a full backup of all parameters (NC, PMC, and Diagnostics) to a PCMCIA card or USB drive. fanuc 9900 parameter list
FANUC CNC systems are known for their immense flexibility, power, and capability, much of which is unlocked through specialized software options. While standard parameters (0-999) configure machine-specific behaviors like speed and acceleration, the serve a distinct and critical purpose: they activate or deactivate optional FANUC functions and hardware features.
While specific machine builders modify these values for custom setups, understanding core FANUC system parameters allows you to troubleshoot system errors, change communication protocols, and optimize machine performance. The Core Concept of FANUC System Parameters
: Change the required bit and press INPUT . A power cycle is usually required for changes to take effect. Reference Documentation
Power off the main CNC control enclosure switch, wait 30 seconds for the capacitors to fully drain, and boot the machine back up. Alarm P/S 101 (Please Clear Memory) These are arguably the most used parameters in this range
Altering 9900 series parameters without authorization carries significant risk:
What are you trying to configure or resolve? Are you getting a specific error code on your screen?
If the data is corrupted, the only way to get the system past Alarm 9900 is to wipe the SRAM clean and reload your original factory backups. In the Boot System Menu, navigate to .
: Press the SETTING function key on the MDI panel. Press the SYSTEM key and type 3202 to find the parameter
Enabling a feature like a 4th axis or specific interpolation without the correct hardware or supporting parameters can cause erratic machine behavior. Essential Backup Protocol
When editing macro programs (O9000 - O9999), always leave comments inside the code. This will save you (or the next technician) hours of head-scratching when troubleshooting. Conclusion
Most 9900 parameters require a cold start. Turn off the main breaker of the machine tool, wait 30 seconds for the capacitors to discharge fully, and turn it back on. Troubleshooting Common 9900 Parameter Alarms