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49.1 GENERAL DESCRIPTION . . . . . . . . . . . . . . 49-1

49.2 SPECIFICATIONS . . . . . . . . . . . . . . . . . 49-2

49.2.1 OUTPUTS . . . . . . . . . . . . . . . . . . . 49-2

49.2.2 OUTPUTS . . . . . . . . . . . . . . . . . . . 49-2

49.2.3 Manual Input . . . . . . . . . . . . . . . . . 49-3

49.2.4 Front Panel Adjustments . . . . . . . . . . . 49-3

49.2.5 CAMAC COMMANDS . . . . . . . . . . . . . . . . 49-4

49.2.6 Visual Indicators . . . . . . . . . . . . . . 49-5

49.2.7 Interrupt Structure . . . . . . . . . . . . . 49-5

49.2.8 Drawing Package Number . . . . . . . . . . . . 49-5

49.2.9 Responsible Company . . . . . . . . . . . . . 49-5 CHAPTER 49 STEPPING MOTOR CONTROLLER AND DRIVER (SMC)

49.1 GENERAL DESCRIPTION The model SMC-24 is a self-contained stepping motor controller and driver all housed in a single-width CAMAC Module. It features an adjustable, linear acceleration and deceleration to provide an efficient method of driving high torque loads at their maximum speed. the maximum speed is adjustable from 50 pps, with other ranges available. The four drivers are capable of switching up to four amps per phase at a maximum of 28 volts, with the high current option capable of over 6 amps. All components required to drive this load are internal with the exception of the current limiting resistors which are determied in each application by the motor voltage and current. Three external, high level logic inputs are used to test the status of the external system, a clockwise limit, counterclockwise limit, and an external signal used to indicate power is being applied to the motor. The actual motor power is also monitored with an opto-isolator. Logic is provided that will inhibit the driver if a limit signal is received and the motor is requested to step in that direction. The number of steps is determined by a 24 bit command word that is in two's complement. Bit 24 determines direction and the remaining 23 bits contain the number of steps to be performed. Two sets of outputs are provided. One is the CW and CCW signals and the other is a pulse train and direction bit. These may be used to monitor the performance of the module or to drive external motor dirvers when higher power is required. The ability to used the modules drivers is also possible. High threshold CW and CCW inputs are provided that only use the moudles drivers and limit inputs. The motor may also be driven manually by a front panel switch. This feature provides the abilility to move the motor without the system working. A remote mode is also available via a front panel remote connector. This allows the motor to be operated remotely from the module, possibly at the motor site itself. The motor can be driven CW and CCW and its speed can be adjusted. the remote mode is interlocked with the limit inputs for protected operation. A pause mode is also available that provides the ability, once a cycle is started, to stop and start the motor progammably without losing position information. An interrupt structure is also provided to improve system integration.



49.2.1 OUTPUTS Motor Drivers Four Phase, Unipolar Drive, internally biased, capable of switching 2 amps at 28 volts, or 4 amps with the external bias pins connected. Internal Motor Power +24 volts from the dataway is available at the coneected to drive the motor. This is fused at 1 amp. Frequency Test Point A test point is available on the front panel and a pin in the output connecter to monitor the frequency of the output signals. Logic "0" 2.5 volts Logic "1" .5 volts Acceleration Test Point A test point is available on the front panel and a pin is available in the output connector to monitor the acceleration time. Logic "0" 2.5 volts Logic "1" .5 volts CCW Output A TTL pulse, Logic "1" = 0 Volts, to monitor counterclockwise steps. Motor steps on trailing edge of pulse. CW Outputs A TTL pulse, Logic "1" = 0 Volts, to monitor clockwise steps. Motor steps on trailing edge of pulse. Active pulse A train of pulses, the "OR" of the CW and CCW outputs is provided. Frequency A TTL signal representing the pulse train being used by the driver. Direction A TTL signal that indicates direction CW = "0" High and CCW = "1" Low. Active A TTL level signal that indicates when a cycle is in progress. 0 volts = unit active.


STEPPING MOTOR CONTROLLER AND DRIVER (SMC) Page 49-3 Clockwise Limit, Logic "0" = 8 volts minimum Counterclockwise limit, Logic "1" = 6 volts maximum External Power These high threshold inputs are all normally in the logic "1" state, thus both a limit signal or a broken wire would indicae an abnormal condition. CW Input The module can be driven externally In the CW direction by a high threshold signal, (Logic "1" zero volts). The motor steps on the trailing edge of the pulse. CCW Input The module can be driven externally in the CCW direction by a high threshold signal (Logic "1" zero volts). The motor steps on the trailing edge of the pulse Stop Input A TTL level signal, Logic "1" (0 volts) will abort the cycle and reset the module.

49.2.3 Manual Input Manual Control A three position locking toggle switch is available to step the motor in the CW or CCW direction. An off position is provided to disable this feature. The switch gates the internal clock (approx. 50 hz) to step the motor. This switch is gated with the CW and CCW limits so that the motor cannot be driven into a limit condition.

49.2.4 Front Panel Adjustments Acceleration/ This multi-turn pot adjusts the accel- Deceleration eration, and equal deceleration, time from 20msec. to 2sec. (other ranges available). Maximum Frequency This multi-turn pot adjusts the maximum frequency from 50pps to 2000pps, other ranges available.


49.2.5 CAMAC COMMANDS F0 A0 Reads count register onto Read lines 1-24, returns Q=1. F0 A1 Reads status register onto Read lines 1-8, returns Q=1. R1 = External Power Status = 1 R2 = Clockwise Limit R3 = Counterclockwise Limit R4 = Counter Equals Zero R5 = Internal +24 volts, Off R6 = Driver Powered R7 = Modules Active R8 = Module In Pause Mode F1 A15 Reads module identity in BCD 00.240.0 F8 A15 Tests LAM, if set and unit is enabled it will respond with Q = 1. F10 A15 Resets LAM flip-flop. F16 A0 S1 Loads two's complement data into count register from write lines W1-24. Strobe S2 initiates the cycle. Note that the limit switches and bit "24" must not be in conflict or the cycle will not begin and a Q=0 will be returned. Resets LAM flip-flop. F24 A0 Stops motor, retains position information, can be used only when system is active. F24 A15 Disables L response. F25 A0 Stops motor, aborts cycle, Resets unit. F26 A15 Enables L response. F27 A0 Tests the status word to determine if module is ready for another operation. Q=1 if external power status equals one and counter equals zero and stepping motor is not in a limit position. F27 A1 Tests contents of count register and generates Q=1 if the counter is zero. X Response X=1 for all commands. S2 and Power Up Resets count register, disables LAM response, and resets LAM flip-flop.


49.2.6 Visual Indicators "N" To indicate module is addressed. CW To indicate a clockwise limit. CCW To indicate a counterclockwise limit. Drive Power Driver is powered. Active The module is performing an operation. CTR = 0 The counter is at zero.

49.2.7 Interrupt Structure A LAM flip-flop is provided that is set by either limit condition, CW or CCW, or when the counter goes to zero indicating the end of a cycle. If this unit is enabled an interrupt will be generated on the L line. This signal is inhibited when the module is being addressed on its N line. Power requirements: +6 volts, 740ma +24 volts, 35ma -24 volts, 35ma Size: #1 CAMAC module Temperature Range: 0 degrees to 50 degrees C Connector: Driver Cannon DD50P, mating connnector Cannon DD50S Remote Cannon DE9P, mating connector Cannon DE9S

49.2.8 Drawing Package Number 233-105

49.2.9 Responsible Company Joerger Enterprises, Inc.

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Contact (until Aug. 15, 1996): Jeffrey Miller
Owner: Bob Sass

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