Here is the Feature / List of Fanuc OT 900 Parameters.
In Fanuc OT (and many 0-series controls), parameters 900–999 are "Option Parameters" or "Machine-Specific Parameters".
They are NOT standardized across all machines — their exact meaning depends on the machine tool builder (Mori Seiki, Haas, Nakamura, Okuma, Leadwell, etc.).
However, there is a common core set of option bits for Fanuc 0T (Model A/B/C). These are typically set at the factory and should not be changed without a backup.
Marco was a CNC maintenance engineer for a mid-sized automotive parts plant. At 11:47 PM, his phone rang. It was Diego, the second-shift supervisor. fanuc ot 900 parameter list
“Marco, the Takumi lathe with Fanuc OT control is dead. Alarm 910 – RAM parity error. I powered it down and back up. Now it’s just a blue screen with ‘Not Ready’.”
Marco sighed. He knew the drill. When a Fanuc OT (old but reliable, released in the mid-1980s) throws a 910 or 911 alarm, the SRAM memory has corrupted. And when that happens, the 900 parameters—the hidden key to the machine’s soul—are often wiped.
| Bit | Name | Function | | :--- | :--- | :--- | | 0 | RMT | Remote buffer (high-speed DNC via RS-232) | | 1 | IPR | Index table control (for sub-spindle or turret indexing) | | 2 | MUL | Multiple PLC control | | 3 | DRL | Drill cycle customizations | | 4 | S4D | 4-speed spindle control | | 5 | AI | AI advanced preview (high precision) | | 6 | PRO2 | Program protect (key-lock override) | | 7 | ATB | Automatic tool compensation (G36/G37) | Here is the Feature / List of Fanuc OT 900 Parameters
| Bit | Function | |------|-----------| | 7 | DNC drip-feed baud rate override | | 6 | Remote buffer (32K) enable – required for complex programs | | 5 | High-speed serial (RS-422/RS-232C) | | 4 | Tape mode without parity check | | 3-0 | Communication protocol version |
If your machine has a small memory but a large program, check Parameter 902, Bit 7 (DNC). If set to 0, change it to 1, and you can use Tape Mode with # or % for continuous RS-232 streaming.
Many second-hand lathes come with Macro B disabled. Check 903.0 = 1. If zero, set it to 1, and suddenly you can use #100 = #101 + 1 and WHILE [#1 LT 10] DO1. The Midnight Call: A Tale of the Missing
| Bit | Function | |------|-----------| | 7 | Axis 1 (X) servo type: 0 = analog (±10V), 1 = digital serial (FANUC α/β) | | 6 | Axis 2 (Z) servo type | | 5 | Separate detector for X axis (0 = motor encoder only, 1 = scale feedback) | | 4 | Separate detector for Z axis | | 3 | High-gain servo mode (0=off, 1=on) | | 2 | Torque limit enable | | 1-0 | Axis scaling factor (pitch error compensation) |
| Bit | Name | Function | | :--- | :--- | :--- | | 0 | SHP2 | Shop floor programming 2 | | 1 | NUR | NURBS interpolation (spline machining) | | 2 | QVS | Quick view solid (3D graphics) | | 3 | CLK | Clock function (#3001 time variables) | | 4 | BSK | Block skip (/) function extension | | 5 | PCH | Punching cycle pack | | 6 | SCB | Skip cycle block | | 7 | CAM | Cam cycle (for hydraulic cam machines) |
| Bit | Function | |------|-----------| | 7 | Critical: 0 = PMC ladder edit disabled, 1 = enabled (use with extreme caution) | | 6 | Parameter write via MDI disable | | 5 | Backup ROM writing enable | | 4 | CNC data save to memory card | | 3 | Boot system modification lock | | 2-0 | Reserved (usually 000) |