The Heidenhain TNC 150 control is a proven industry workhorse. Establishing stable DNC data transfer requires precise RS232 serial port configuration. When adjusting machine parameters (MP92 and MP71) and selecting your handshake protocol (RTS/CTS or Xon/Xoff), ensure your DNC software settings match the control exactly to prevent framing errors, parity mismatches, or buffer overflows. Common configuration pitfalls often stem from baud rate discrepancies or misaligned flow control logic between the PC and the control. Always verify that your stop bits and character parity settings are consistent across both systems to ensure reliable program transmission. Proper cable shielding is equally critical to prevent signal noise interference during high-speed data transfer in shop floor environments.
| Parameter | Value | Comments |
|---|---|---|
| MP92 | 1 | Select Multi Func. |
| MP71 | 3 | - |
| BaudRate | 2400 | (Same as in the DNC software) |
Select RTS/CTS flow control in your DNC software. The software must be configured to insert STX and ETX codes into the data stream; in easyDnc 4.0, this is accomplished in the DNC setup window by clicking "Advanced" and selecting these options from the dropdown menus.
ASCII Start Code = STX (02)
ASCII End Code = ETX (03)
The cable diagram shown below supports both xOn/xOff (DC1/DC3) and RTS/CTS (hardware flow control) and is therefore recommended for most installations.
However, if you are certain your CNC does not require flow control—or strictly requires only xOn/xOff—a simplified 3-wire cable configuration can be used. View the diagram here.
RS232 Cable: 9-pin computer to 25-pin CNC
