Compatible Devices
Yamaha RCX Series
Ethernet driver requires RCX Ethernet interface
Verified Device
Yamaha RCX144
Accessing Data
The programmer is responsible for ensuring only valid values are sent to the RCX controller.
- Errors from the controller are stored in Latest Error Message
- This should be mapped to a string tag (Packed High-to-Low)
- The message includes both:
Accessible Data
| Prefix |
Description |
Data Type |
Range |
| DI |
Parallel Inputs |
Byte |
0–177 (Octal) |
| DO |
Parallel Outputs |
Byte |
0–127 (Octal) |
| MO |
Internal Auxiliary Outputs |
Byte |
0–27 (Octal) |
| TO |
Timer Outputs |
Byte |
1 Byte |
| LO |
Arm Lock Outputs |
Byte |
1 Byte |
| SI |
Serial Inputs |
Byte |
0–27 (Octal) |
| SO |
Serial Outputs |
Byte |
0–27 (Octal) |
| SIW |
Serial Word Input |
Word |
2–15 |
| SOW |
Serial Word Output |
Word |
2–15 |
| SGI |
SG Integer Variables |
Long |
0–7 |
| SGR |
SG Real Variables |
Real |
0–7 |
| MSPEED |
Manual Speed |
Byte |
1–100 |
| ASPEED |
Automatic Speed |
Byte |
1–100 |
Command Registers (Write Only)
Commands execute when the bit is set and must be cleared before reuse.
| Prefix |
Description |
| AUTO |
Set AUTO Mode |
| PROG |
Set PROGRAM Mode |
| MAN |
Set MANUAL Mode |
| SYS |
Set SYSTEM Mode |
| RESET |
Reset Program |
| RUN |
Execute Program |
| STEP |
Execute One Line |
| SKIP |
Skip One Line |
| NEXT |
Execute to Next Line |
| STOP |
Stop Program |
| EMGRST |
Reset Emergency Stop |
| CHGTSK |
Switch Task |
Motion Commands (Require Parameters)
| Prefix |
Description |
| ABSADJ |
Move to Absolute Reset |
| ABSRST |
Absolute Reset |
| ORGRTN |
Return to Origin |
| INCH |
Manual Inch |
| JOG |
Manual Jog |
⚠️ May suspend communications during execution [g3-yamrcx-3- | Word]
Time Sync
| Prefix |
Description |
| DATE |
Sync Date |
| TIME |
Sync Time |
Additional Write Registers
| Prefix |
Description |
Notes |
| UNIT |
Set Coordinate Units |
0=pulses, 1=mm, 2=mm/degrees |
| ACCESS |
Set Access Level |
0–3 |
| EXELVL |
Execution Level |
0–8 |
| SEQUENCE |
Sequence Execution |
0=off, 1=on, 3=on w/reset |
| TEACH |
Teach Point Data |
0–9999 |
Read-Only Status Data
| Prefix |
Description |
Tag Type |
| WHERE |
Current Position |
Integer |
| WHRXY |
XY Position |
Real |
| MODE |
Mode Status |
String |
| ARM |
Arm Status |
String |
| SERVO |
Servo Status |
String |
| SPEED |
Speed Status |
String |
| UNITS |
Units |
String |
| VER |
Version Info |
String |
| EMG |
Emergency Stop Status |
Integer |
Breakpoint & Program Control
- Use:
-
BRKPT (breakpoint number)
-
BRKLN (line number)
- Trigger using BREAK bit
- Must clear bit before reuse
Program switching uses:
-
SWI → assign new program name
User Commands
| Register |
Function |
| USER |
Send custom command |
| RESP |
Capture controller response |
New Data Access Features
v1.02+
| Prefix |
Description |
| SERVOC |
Servo Command (1=ON, 2=OFF, 3=FREE) |
| MOVE |
Absolute Move |
| DRIVEI |
Relative Move |
| PMOVE |
Pallet Move |
v1.03+
| Prefix |
Description |
| Pn |
Current Position |
| PnSet |
Set Position |
| PnCmd |
Execute Position |
| CTRLC |
Interrupt Control |
v1.04+
| Prefix |
Description |
| SERVOC_A |
Servo All Axis |
| ABSRST_A |
Reset All Axis |
v1.05+
| Prefix |
Description |
| LOGON |
Login (Ethernet only) |
| LOGOFF |
Logout |
Ethernet Notes
- Change RCX port from Telnet for better performance
- Set Echo to Invalid
- Default credentials:
- User: USER
- Password: PASSWORD
Timeouts should be ≥ 1/10 of command duration for motion commands
Cable Information
Serial
| G3 RS232 |
RCX RS232 |
| 2 - RX |
3 |
| 3/4 - COMM |
5 |
| 5 - TX |
2 |
Pins 7 & 8 must be connected on RCX side
Ethernet
Standard 10-Base-T Ethernet Cable
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