Most Heidenhain controls are capable of communicating at baud rates between 110 and 38400. But it is recommended, when feeding in to CNC memory (ie not drip feeding), that the speed is quite low at 4800 or lower.

However, if you need to drip feed large complex programs then a higher speed of 19200 will almost certainly be required and you should use the Heidenhain Blockwise Protocol if your machine supports it.

Many Heidenhain TNC controls can be configured to use the Heidenhain Blockwise Protocol for reliable high speed drip feeding of programs that exceed the memory capacity of the machine.

On many Heidenhain machines such as TNC360, 425, 2500 etc. the Blockwise Protocol is Enabled via parameter 5030. (Check the documentation for your specific machine.)

0 = Blockwise Disabled.

1 = Blockwise Enabled. Uses Heidenhain Blockwise Protocol.

Instructions below assume you are using RemoDNC where the DNC Setup has options:-

Mode = Heidenhain
FlowControl = Blockwise

RemoDNC also has 'Wait' and 'Repeat' options but the first time you drip feed using RemoDNC we would suggest that Wait and Repeat are disabled. Prepare the DNC to send but do not click the 'Send' button. Go to the CNC, prepare the machine and and begin the machining process - then, while the CNC is waiting, go back to the DNC and click Send. The machining process should start.

Once you know that the drip feed works correctly you can configure wait and repeat options if required.

DNC Wait means that you can press the DNC Send button before the machine is ready but the DNC will wait for the machine to be ready.

DNC Repeat, in conjunction with 'Wait' means that the DNC will keep repeating the same program without the machine operator needing to go back to the computer.