2. Model Naming

• JANCD: Yaskawa standard prefix for CNC/robot control boards

• CG: Graphic & Communication (display + serial I/O)

• 20: Early hardware generation (separate from CG01–CG06 line)

• B: Revision B (component and firmware tweaks over CG20)

3. Key Specifications (vs CG20)

• Form Factor & Power: Same as CG20—5 V DC / ±12 V DC, standard slot, ~320×150×30 mm, 0.7 kg

• Processor: Same dedicated 2D graphic CPU (no 3D)

• Display: Monochrome CRT/LCD (VGA-compatible, no color)

• Communication:

  • CG20: RS-232 only

  • CG20B: RS-232 + minor firmware fixes for serial stabilityYaskawa

• Protection: Improved ESD/noise immunity (component upgrades)

• Operating Temp: 0–50 °C, IP20 (same as CG20)

4. Core Functions

1. Display Control: Drives monochrome HMI for CNC programs, coordinates, alarms, diagnostics

2. Operator Panel I/O: MDI keyboard, manual pulse generator (MPG), function keys

3. Serial Communication: RS-232 for program upload/download, peripheral connection

4. System Offload: Reduces main CPU load for graphics and I/O scanning

5. Compatibility & Applications

• Compatible Systems: YASNAC J10/J20/J30 CNC; early Motoman XRC robots

• Compatibility: 100% pin-compatible with JANCD-CG20 (direct swap)

• Incompatible With: CG01–CG06 series (different hardware/firmware)

• Use Case: Legacy machine repair/replacement; not for new builds

6. CG20 vs CG20B Summary

7. Notes

• Status: OEM discontinued; source tested refurbished units

• Limitations: No color display, no Ethernet, no modern protocols

• Recommendation: Use CG20B as a direct upgrade/replacement for failed CG20; for modern systems, select CG06 or newer.