Geckodrive

GM215 MOTION CONTROLLER MANUAL

This manual covers the GM215 when it's used as a motion controller and motor drive. Go to the GM215 STEP MOTOR DRIVE MANUAL if the GM215 is used as a conventional STP/DIR input step motor drive.

SWITCH SETTINGS AND CONNECTOR WIRING

 

Figure 3

GM215 SETUP FOR MOTION CONTROLLER MODE

CAUTION: The following switch settings and their function only applies to the Motion Controller Mode. The same switches have completely different functions in the Step Motor Drive mode. Turn the power supply 'OFF' and take care to set the switches to their correct settings when changing the operating mode.

STEP 1: SELECT MOTOR DRIVE MODE  SW1 'OFF' Select motion controller mode operation.

STEP 2: SELECT MOTOR SIZE                 SW5 ‘ON’ The motor is a NEMA-23 size or smaller.

                                                                SW5 'OFF' The motor is a NEMA-34 size or larger.

STEP 3: SELECT AXIS NAME

The axis name tells a GM215 which commands and communications apply to it and which it can ignore.

X AXIS     SW3 'ON'                 Y AXIS     SW3 'ON'                Z AXIS     SW3 'OFF'                               W AXIS    SW3 'OFF'                                              

                SW4 'ON'                                SW4 'OFF'                               SW4 'ON'                                                SW4 'OFF'

STEP 4: SELECT OPERATION The Motion Controller has 2 operating modes: RUN and EDIT.

RUN PROGRAM      SW2 'ON'               

In RUN PROGRAM mode, one or more G215s execute a user program stored in Flash ROM without requiring a computer connection. A computer connection can be used if it is necessary to monitor program execution. The GM215 inputs and outputs are used to coordinate motion with switches, sensors and other GM215s.

EDIT PROGRAM      SW2 'OFF'              

The EDIT PROGRAM mode is used to edit an existing user program or to write new user program. This mode requires a serial connection (RS-485) to a computer used to edit or write the program.

Edit mode can be used as a debug tool. Each line of code cab be single stepped. For high performance behavior, please use RUN mode.

Program lines can be sent from the computer to the G215 for immediate execution. For instance, sending a command to 'home' an axis will result in the axis' step motor immediately moving the mechanism to the home location.

Once a user program is written or, a written program is modified in editing, the user program can be flashed to ROM on the target GM215 and/or stored to file on the computer.

THIS COMPLETES THE SWITCH SETUP

CN2 CONNECTOR ASSIGNMENTS

Terminals 1, 2 and 3 are opto-isolator LED anode inputs in series with 200 Ohm current limit resistors. The LED cathodes go to the COMMON terminal. The inputs work with 2.5V, 3.3V and 5V logic levels. Minimum logic 1 input current is 2 mA. Terminals 5, 6 and 7 are three opto-isolated collector outputs that have a 10 mA current sink rating and their emitters go to the COMMON terminal.

       Terminal           Name                      Function

 

                 1             IN1                          INPUT

                 2             IN2                          INPUT

                 3             IN3                          INPUT

                 4             COMMON

                 5             OUT1                       OUTPUT

                 6             OUT2                       OUTPUT

                 7             OUT3                       OUTPUT

                 8             ANALOG GND         ANALOG GND

                 9             ANALOG IN             ANALOG INPUT

                10            RS485 A                   SERIAL PORT

                11            RS485 B                   SERIAL PORT

                12            RS485 COM             SERIAL PORT GROUND

IN 1 (TERMINAL 1)

This is a low-speed opto-isolated general purpose input. A logic '1' signal turns the input 'ON'. The signal ground is the COMMON terminal (term 4). At RUN mode its dedicated function is RESET. (REF FIGURE 5)

IN 2 (TERMINAL 2)

This is a high-speed opto-isolated general purpose input. A logic '1' signal turns the input 'ON'. The signal ground is the COMMON terminal (term 4). Its dedicated function is the home switch input if the HOME command is used.  (REF FIGURE 4)

IN 3 (TERMINAL 3)

This is a high-speed opto-isolated general purpose input. A logic '1' signal turns the input 'ON'. The signal ground is the COMMON terminal (term 4). It has no dedicated function.

COMMON (TERMINAL 4)

This terminal is the signal ground for IN 1, IN 2, IN 3, OUT 1, OUT 2 and OUT 3 opto-isolators.

OUTPUT 1(TERMINAL 5) GENERAL PURPOSE OUTPUT 

OUTPUT 2(TERMINAL 6) GENERAL PURPOSE OUTPUT 

OUTPUT 3(TERMINAL 7) GENERAL PURPOSE OUTPUT

ANALOG INPUT (TERMINAL 8 & 9) analog control input

RS485 (TERMINALS 10, 11, 12)

These terminals are used by the RS-485 transceiver. The RS-485 COM terminal connects to the GM215 circuit ground through a 33 Ohm resistor used to limit ground loop currents. All GM215s using the RS-485 serial interface must share a common power supply ground. The A input has a 3K pull-up resistor to 3.3V while the B input has a pull-down 3K resistor to ground. These terminals aren't opto-isolated.

 

MULTI-AXIS POINT-TO-POINT MOTION

Point-to-point multi-axis motion is used when it does not matter what path is taken to a coordinate location. This is perfectly acceptable in many application because point-to-point motion takes the shortest possible time moving to a new location.

Each axis can use its own programmed accelerate, velocity and destination values for motion. The path taken to the destination probably won't be in a straight line because each axis' acceleration, velocity and destination can be different so each axis will take a different amount of time moving to the new location. All of the axis must finish moving before they can move to the next programmed location.

MULTI-AXIS VECTOR MOTION

Unlike point-to-point motion, a vector motion path is along a straight line from the last coordinate location (previous x, y, z) connecting to the next coordinate (next x, y, z). The rate of acceleration and velocity is independent of the vector direction. Oftentimes the coordinates are short line segments that, when concatenated, linearly approximate arbitrary 2D or 3D curves.

Vector motion requires all GM215s begin and finish executing each vector segment at precisely the same time and this requires that all GM215's microprocessor clocks be phase locked to the master x-axis clock. Besides communication tasks, the master x-axis GM215 uses the RS-485 serial bus to transmit a synchronizing signal to all slave axis GM215s.

For reason of simplicity, each axis is programmed with exactly the same user program. Each GM215 calculates the vector length from the coordinates stored in the program but only extracts the vector component that matches that motion controller's designated name. The vector component is then processed by a motion control algorithm and the results are sent to the motor drive section of the GM215. Each GM215 then drives its attached axis motor and all the axis motor's movements combine to reconstitute the vector as a 2D or 3D motion in the motor-driven mechanism.

Figure 4: How to wire the HOME switches

Figure 5: How to wire the RESET switch for RUN mode

I/O SCHEMATIC

The opto-isolator LED series current limit resistors are 200 Ohms on the IN1, IN2, and IN3 inputs. The input current is 17mA at +5A, 9mA at +3.3V and 2mA at +2.5V. The minimum operating input current for all inputs is 1.6mA. IN1 is a low-speed opto-isolator having a 50uS propagation delay. IN2 and IN3 are high-speed opto-isolators and have a 1uS propagation delay. OUT1, OUT2, and OUT3 are low-speed opto-isolators having a 50uS propagation delay.