3 hsc output (high speed counter match), 4 stepper function – Horner APG XL7 OCS User Manual

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XL7 User Manual

11.5.3 HSC Output (High Speed Counter Match)

When either Q1 or Q2 is configured for HSC Output operation, HSC1 or HSC2 turns on, off or toggles

based on a comparison between the counter accumulator and match registers. See details above in the

high speed input section.

11.5.4 Stepper Function

The XL7 supports two stepper functions, one on each high speed output.

The Stepper requires five parameters (%AQs) to be set for operation. These parameters may be set at

run-time but are ‘latched’ when the stepper is commanded to start:

Start Frequency

(cycles per second)

This value sets the frequency for the first cycle during the acceleration phase and

the frequency of the last cycle during the deceleration phase. When an

acceleration or deceleration count is specified, the Start Frequency must be

greater than 0 and must not exceed the run frequency or an error is generated.

Run Frequency

(cycles per second)

This value sets the frequency for the last cycle during the acceleration phase, the

consistent frequency during the run phase, and the frequency of the first cycle

during the deceleration mode. The Run Frequency must be greater than 0 and

must not exceed 5000 cycles/sec. or an error is generated.

Acceleration Count

This value sets the number of cycles to occur within the acceleration phase. The

frequency of the cycles within this mode will vary linearly between the specified

Start and Run frequency. The Accel count must not equal 1 or an error is

generated. Setting this value to zero disables this phase.

Run Count

This value sets the number of cycles to occur within the run phase. The

frequency of the cycles within this mode is constant at the specified Run

frequency. The Run count may be any value. Setting this value to zero disables

this phase.

Deceleration Count

This value sets the number of cycles to occur within the deceleration phase. The

frequency of the cycles within this phase will vary linearly between the specified

Run and Stop frequency. The Decel count must not equal 1 or an error is

generated. Setting this value to zero disables this phase.

The stepper provides two Boolean registers to provide stepper status:

Ready/Done

A high indication on this register indicates the stepper sequence can be started

(i.e. not currently busy).

Error

A high indication on this register indicates that one of the analog parameters

specified above is invalid or the stepper action was aborted before the operation

was complete. This register is cleared on the next start command if the error

was corrected.

The stepper requires one discrete register to control the stepper action. Setting this register starts the

stepper cycle. This register must remain set to complete the entire cycle. Clearing this register before

the cycle is complete aborts the step sequence and sets the error bit.

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