Programming Overview

The RMC has a rich set of pre-programmed high-level motion commands. In addition, it can easily be programmed to perform simple motion sequences or complex actions. With the RMC features listed below, motion applications can be done entirely within the RMC, or in conjunction with a PLC.

Note:
In order to run User Programs or the Program Triggers, the RMC must be in RUN mode. See the RUN/Program Mode topic for details.

Programming Examples

See the Programming Examples topic for tips and examples of programming the RMC.

Commands

The commands are the building blocks of RMC programming. Commands tell the RMC what to do. For a list of commands, see the Command List topic. Commands may be issued from the following places:

From RMCTools using the Command Tool.
From a PLC or other host controller via the communication port.
From a User Program.

See the Issuing Commands topic for details on issuing commands.

User Programs

A User Program carries out a sequence of commands without requiring a PLC or other controller. This allows the RMC to respond to events within its control-loop time rather than the scan rate of the PLC. It also reduces the controller programming required.

A User Program consists of multiple steps. Each step can issue a command on one or several axes. The series of steps are linked together in sequences. The link types allow branching and looping, waiting for conditions and many other features. An RMC controller may execute several User Programs simultaneously.

User Programs run on Tasks. One Task can run one User Program at a time. The RMC75 has 4 tasks and can run 4 User Programs simultaneously. The RMC150 has 10 tasks and can run 10 User Programs simultaneously.

For details on creating and running User Programs, see the User Program topic.

Mathematical Expressions in User Programs

Advanced math operations using expressions are also possible in user programs. RMCTools provides a rich set of functions and operators, and allows for user-defined functions.

Program Triggers

You can set up program triggers to automatically start user programs when some condition becomes true. For example, you can trigger a user program when a discrete input turns on, or a variable becomes a certain value. This is a good way to start user programs from a PLC.

See the Program Triggers topic for details.

Variables

Variables make the User Programs very flexible. Variables can be used to effortlessly change programs, make programs readable, and easily influence User Programs via a PLC. Variables may be used in command parameters, the Expression (113) command, and several Link Types.

Variables can be individually selected to be retentive. The Current Value of retentive variables will be retained between power cycles without requiring a Flash update. This is useful for retaining data such as setpoint positions, machine cycle counters, and recipe data.

Retentive variables are only available on the RMC75E (version 1.4A or newer) and the RMC150E and require firmware 3.30.0 or newer.

See the Variables topic for details.

Discrete I/O

The discrete I/O on the RMC can be used to control the programming, and the programming can control the discrete I/O. See the Discrete I/O topic for details.

Programming from External Systems

The RMC can be controlled from a PLC or other host controller. It can be done in the following ways:

Entirely with a PLC

A PLC can exercise complete control over the RMC by issuing commands to it. The RMC supports many communication protocols, such as DF1, Modus/RTU and PROFIBUS.

With the RMC and PLC (or HMI)

The RMC can be programmed using a combination of a host PLC (or HMI) and User Programs. This allows fast and time-critical sequences to be implemented in the User Program (which executes at the RMC loop time), while less time critical functions are handled via the PLC.

For details on using the RMC with an HMI, see the Communicating with HMIs topic.

Program Size and Time

See the Program Capacity and Time Usage topic for details.