1. General

• Part Number: JANCD‑SP20（SP20B‑01、SP20B‑02）

• Manufacturer: Yaskawa Electric / Motoman Robotics

• Function: CRT & keyboard controller board（operator panel I/F）

• Applicable Systems:

  • Motoman ERC robot controller

  • YASNAC LX3 / MX3 CNC（with MDT‑948B‑3 monitor）

• Status: Discontinued（only used / refurbished / surplus）

• Origin: Japan

2. Specifications

• Power: +12 V DC（from backplane）

• Current: ~0.5 A

• Operating Temp: 0 °C to 55 °C

• Storage Temp: −20 °C to 60 °C

• Humidity: ≤95% RH（non‑condensing）

• Interfaces:

  • 20‑pin flat cable：connects to JANCD‑SP19 keypad

  • CRT video port：drives monochrome CRT

  • System bus：communication with ERC / LX3 / MX3 CPU

3. Main Functions

• Keyboard scanning: Reads SP19 key matrix, debounces, encodes key codes

• CRT display control: Outputs text / status to CRT monitor

• Panel I/O: Processes front‑panel switches, mode keys, and LED indicators

• System bridge: Transfers data between keypad/display and main controller

4. Model Variants

• SP20B‑01: Early version，for LX3 CRT/keyboard only

• SP20B‑02: Standard version，compatible with ERC + LX3/MX3，matched to SP19 keypad

5. Compatibility

• ✅ Motoman ERC robots

• ✅ YASNAC LX3 / MX3 CNC（MDT‑948B‑3 monitor）

• ❌ Not compatible: XRC、NX100、DX100、DX200 and later controllers

6. Common Troubleshooting

• Keypad dead: Check 20‑pin cable, SP19 membrane, and board fuse

• Key ghosting / jumbled input: Usually worn SP19 keypad; occasionally scanning circuit fault

• CRT no power: Check +12 V supply, CRT cable, and video driver circuits

• Board not recognized: Clean gold fingers, re‑seat in backplane slot

7. Installation Notes

• Power off and wait 5 minutes for discharge

• Use ESD protection（wrist strap）

• Insert into designated backplane slot and secure

• Connect SP19 flat cable and CRT cable

• Power on and test keypad, display, and LEDs