Some calculations may take a long time to be performed, making it necessary to interrupt these tasks to regain control of the calculator. newRPL provides two different ways to interrupt the system.

This is the most common way to interrupt programs. It is performed by pressing simultaneously ON^hold-A^hold-C^hold. The screen will show a message and the soft menu will display several options.

• Cont will continue the task as if it had never been interrupted (press A to select this choice);
• Exit will end the current RPL program and return to the stack (press B to select this choice). Notice that this option might leave the stack with objects the program was using internally, and the user will need to clean up the stack manually;
• *Warmstart* will completely restart the RPL engine (press either LS^hold-C, RS^hold-C, LS^hold-D or RS^hold-D then release the keys to select this choice). A warmstart is only needed if the running program leaves the system unusable;
• **Reset** not only restarts the RPL engine, but also causes a reset of the calculator hardware (press either LS^hold-E, RS^hold-E, LS^hold-F or RS^hold-F then release the keys to select this choice). This is only necessary if the hardware malfunctions or does not respond.

This interrupts the entire system, not only the RPL engine, and it is performed by pressing simultaneously ON^hold-A^hold-F^hold. The screen will show a message and the soft menu will display several options.

• Cont will continue the task as if it had never been interrupted (press A to select this choice);
• *Clear Mem* will completely wipe out the entire memory. This is an unrecoverable procedure, the only way to recover is through backups previously stored in SD card or saved externally through the USB port. For safety, press either AL^hold-LS^hold-RS^hold-C or AL^hold-LS^hold-RS^hold-D in order to clear the memory. Pressing only one of the shift keys will perform a warmstart but not clear the memory;
• **Reset** causes a reset of the calculator hardware (press either E or F while at the same time holding any one of AL, LS or RS to select this choice). This is only necessary if the hardware malfunctions or does not respond.