MCordr Statement

Specifies and displays the moving joint order for machine calibration Mcal. Required only for robots with incremental encoders.

Syntax
(1) MCordr Step1, Step2, Step3, Step4 [, Step5] [, Step6] [, Step7] [, Step8] [, Step9]

(2) MCordr

Parameters

step1
Specify the joints (0 to 9) to be homed in the first step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)
step2
Specify the joints (0 to 9) to be homed in the second step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)
step3
Specify the joints (0 to 9) to be homed in the third step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)
step4
Specify the joints (0 to 9) to be homed in the fourth step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)
step5
Specify the joints (0 to 9) to be homed in the fifth step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)
step6
Specify the joints (0 to 9) to be homed in the sixth step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)
step7
Specify the joints (0 to 9) to be homed in the seventh step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)
Step8
Specify the joints (0 to 9) to be homed in the eighth step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)
step9
Specify the joints (0 to 9) to be homed in the ninth step of the MCal process by a bit pattern (binary value). (see below for bit pattern definitions)

Return Values
Displays current Machine Calibration Order when parameters are omitted.

Description
After the system is powered on, Mcal instruction must be issued prior to any robot arm operation. When the Mcal instruction is issued each of the 4 axes of the robot will move to their respective calibration positions.

Specifies joint motion order for the Mcal command. (i.e. Defines which joint will home 1st, which joint will Mcal 2nd, 3rd, etc.)

The purpose of the MCordr instruction is to allow the user to change the homing order. The homing order is broken into 9 separate steps. The user then uses MCordr to define the specific axes which will move to the calibration position (done with the Mcal command) during each step. It is important to realize that more than 1 joint can be defined to move to the calibration position during a single step. This means that all four axes can potentially be calibrated at the same time. However, it is recommended that the Z joint normally be defined to move to the calibration position first (in Step 1) and then allow the other Axes to follow in subsequent steps. (See Notes below)

The MCordr instruction expects that a bit pattern be defined for each of the 9 steps. Since there are 4 axes, each joint is assigned a specific bit. When the bit is high (1) (for a specific step), then the corresponding joint will calibrate. When the bit is low (0), then the corresponding joint will not calibrate during that step. The joint bit patterns are assigned as follows:

Bit pattern chart

Joint Bit number Binary Code
1 bit 0 &B000001
2 bit 1 &B000010
3 bit 2 &B000100
4 bit 3 &B001000
5 bit 4 &B010000
6 bit 5 &B100000
7 bit 6 &B1000000
8 bit 7 &B10000000
9 bit 8 &B100000000

Notes


  • Difference Between MCordr and Hordr

    While at first glance the Hordr and MCordr commands may appear very similar there is one major difference which is important to understand. MCordr is used to define the Robot Calibration joint order (used with Mcal ) while Hordr is used to define the Homing joint order (used with the Home command).

  • Default MCal Order (Factory Setting)

    The default joint calibration order from the factory is as follows:

  • The joint 3 will home in Step 1.

  • Then joints 1, 2, and 4 joints will all home at the same time in step 2.

  • (Steps 3 and 4 are not used in the default configuration.) The default MCordr values are as follows:

    MCordr &B0100, &B1011, 0, 0
    
  • Z Joint should normally be calibrated first

    The reason for moving the Z joint first (and by itself) is to allow the tooling to be moved above the work surface before beginning any horizontal movement. This will help prevent the tooling from hitting something in the work envelope during the homing process.

  • MCordr values are maintained

    The MCordr Table values are permanently saved and are not changed until either the user changes them or the robot is redefined.


See Also
Mcal

MCordr Statement Example
Following are some monitor window examples:

In this example, the homing order is set in binary as follows

Joint #3 is homed in Step 1, Joint #1 in Step 2, Joint #2 in Step 3, and Joint #4 in Step 4.

>mcordr  &B0100, &B0001, &B0010, &B1000

In this example, the homing order is set in decimal numbers as follows

Joint #3 is homed at the first step, and Joint #1, Joint #2, and Joint #4 are homed at the same time at the second step.

>mcordr  4, 11, 0, 0

This example displays the current calibration order in decimal numbers.

>mcordr
4, 11, 0, 0
>