Configuration Word

Default: 0x0000

This 16-bit word controls the configuration of the module. Bit 0 is the LSB; bit 15 is the MSB.

Bits 7, 12-15 - Transducer Type bits

These bits are used differently depending on the transducer type used. Refer to one of the following topics for details on these four bits:

Bit 11 - Pressure Assign bit

This bit is used only if the RMC has one or more auxiliary pressure or force channels. If such channels are installed, then this bit can be set to indicate that this position axis has an assigned pressure axis. Bits 8 and 9 are used to define the pressure axis assigned.

Bit 10 - Auto Home Re-arm

This bit is for Quadrature axes only. When it is set, the axis will automatically be re-armed after homing. This requires the axis to first be armed using the Arm Home Command. If this bit is cleared after homing, the axis will still be armed. See the Homing a Quadrature Axis topic for details.

Bits 8 - 9 - Pressure Axis Select bits

These bits are used only if the RMC has one or more auxiliary pressure or force channels and bit 11 is set to indicate that this axis has one of the pressure or force channels assigned to it. These bits then select between up to four auxiliary pressure/force channels:

Bit 9	Bit 8
0	0	The first auxiliary pressure/force axis is assigned.
0	1	The second auxiliary pressure/force axis is assigned.
1	0	The third auxiliary pressure/force axis is assigned.
1	1	The fourth auxiliary pressure/force axis is assigned.

It is necessary to assign a pressure axis to a position axis in order to switch between position and pressure control. Refer to Using an Analog Channel as a Pressure Axis for details.

Note: Two position axes cannot be assigned to the same pressure axis. If this does occur, only the first axis to make the assignment followed by the Set Parameters (P) command will succeed in being assigned. Any later attempt to assign the pressure axis will fail with a parameter error.

Bit 6 - Reverse Drive Mode bit

Warning: This bit must be set properly when the Set Parameters command is issued.

This bit determines the relationship between the RMC’s position direction and the drive output direction.

For analog-output axes, setting this bit reverses the polarity of the axis output voltage. Although in many cases the differential drive wires can be swapped on the drive unit, this is not always possible or it may simply be easier to use this bit.

Bit 6
0	The RMC will generate positive drive to increase transducer counts.
1	The RMC will generate negative drive to increase transducer counts.

For stepper-output axes, this bit is used to change the meaning of the Direction output with relation to the axis transducer counts.

Bit 6
0	The RMC will use a low Direction output to increase transducer counts.
1	The RMC will use a high Direction output to increase transducer counts.

Bit 5 - Absolute Mode bit

This mode is intended for use with a two-valve system, one controlling the flow rate and the other the direction. This axis controls the flow-rate valve. The directional valve must be controlled by other means. In this mode, the axis generates a positive drive output regardless of the direction of the move. The drive will not go negative if the motion controller overshoots the target. This is useful for some injection and blow-molding applications.

When the axis is stopped, you must go into open loop mode.

Warning: This bit must be set properly when the Set Parameters command is issued.

Bit 4 - Continue Mode bit

This bit affects what happens when the module loses contact with the Programmable Controller. When this bit is set, the module will finish any move it has started, otherwise it will halt immediately upon detecting loss of contact with the PLC. This is useful for finishing a move that must complete to prevent machine downtime (for example, a partial shot in an injection-molding machine).

Bit 3 - Simulate bit

When this bit is set, the drive output is set to zero and the magnetostrictive transducer inputs are ignored. Internally the Target Position is used as the Actual Position. This mode is used for debugging. (The transducer error bits and LEDS will be cleared.)

Note: Drive output is always 0 volts while in simulate mode; no commands, including open loop, will change this.

Bits 1 - 2 - Prescale Divisor Bits

Prescaling may be desired on systems with long strokes. The prescale bits are used along with the Scale parameter to convert Transducer Counts to Actual Position. The effect is to divide the Scale by 1, 2, 4, or 8. The divide-by factor is specified as follows:

Counts ÷	Bit 2	Bit 1
1	0	0
2	0	1
4	1	0
8	1	1

The advantage of these bits is that they let you maintain a higher resolution in the Scale parameter. For example, a Scale of 31027 and a divide-by of 4 gives an effective scale of 7756.75. Without using the divide-by bits, the Scale would have to be rounded up to 7757, which has less resolution—with a 64" rod, the rounded value would make a 0.002" error at 64". Note: The stroke is always limited to 220 inches due to the 18-bit transducer counter resolution.

These bits must be zero for Resolver modules.

Bit 0 - Integrator Limit

When this bit is cleared, the integrator limit is 20% of full drive. When the bit is set, the limit is 80%. If the integrator tries to go above the limit, the Integrator Windup bit in the status word is set and the integrator value is held at the limit. The integrator limit is designed to prevent the drive output from saturating.

Note: The actual drive output may be reduced based on the values of the Extend Feed Forward and Retract Feed Forward .