Motion Buffer Control

This command manipulates the XBot Motion Buffer, the available options are:

Block: The motion buffer corresponding to the specified XBot will be blocked from sending next command in the buffer to the XBot
Unblock: The motion buffer will be unblocked and the XBot will resume executing commands in its motion buffer
Clear: The buffer of commands for the specified XBot will be cleared

Fieldbus Interface

PMC_MotionBufferCtrl

Inputs

Name	Data Type	Description
Execute	BOOL	Execution of the function block begins on a rising edge of this input.
Level	USINT	0: Block Buffer; 1: Release Buffer; 2: Clear Buffer
XbotID	USINT	ID of the XBot. 0 = All XBots. Real XBot IDs [1,78]. Virtual XBot IDs [100,127]
PM_Controller	PMControllerType	Data structure that specifies which PMC to connect to. There should be only 1 instance of this variable for each connected PMC.

Outputs

Name	Data Type	Description
Done	BOOL	Execution successful. Function block is finished. (Note: Done will not become TRUE if Execute is already FALSE)
Busy	BOOL	Function block is active and must continue to be called.
Aborted	BOOL	Command aborted by another command.
Error	BOOL	If there is an error in processing the command, then Error = TRUE, otherwise, FALSE.
ErrorID	UINT	0x0: All OK. Otherwise, please see PMC Reply Codes.

Ethernet Interface

MotionBufferReturn MotionBufferControl(int xbotID, MOTIONBUFFEROPTIONS bufferOption)

Parameters

Name	Type	Description
xbotID	int	ID of the XBot. Real XBot IDs [1,78]. Virtual XBot IDs [100,127]
bufferOption	enum	BLOCKBUFFER (0) = block buffer; RELEASEBUFFER (1) = release buffer; CLEARBUFFER (2) = clear buffer

Returns

Name	Type	Description
MotionBufferReturn.PmcRtn	PMCRTN enum	ALLOK (0): Command Accepted. Otherwise, please see Ethernet Reply Codes.
MotionBufferReturn. MotionBufferStatus	struct	bool isBufferBlocked: true if buffer is blocked, false if buffer is not blocked int bufferedMotionCount: number of motions stored in the specified XBot’s motion buffer int firstBufferedMotionCmdLabel: command label of the first command in the specified XBot’s motion buffer int lastBufferedMotionCmdLabel: command label of the last command in the specified XBot’s motion buffer int xbotID: ID of the XBot that this return is describing

Conditions

Operating Conditions
Preconditions	XBot is in the Idle state, Obstacle Detected state, Motion state, Stopped state, Hold Position state, or Waiting state.
Postconditions	The XBot’s buffer will be blocked immediately. Since the buffer only contains future commands for the XBot, the current command executed by the XBot will finish executing as normal.

Description

This command manipulates the XBot Motion Buffer, the available options are:

Block: The motion buffer corresponding to the specified XBot will be blocked from sending next command in the buffer to the XBot
Unblock: The motion buffer will be unblocked and the XBot will resume executing commands in its motion buffer
Clear: The buffer of commands for the specified XBot will be cleared

The maximum number of commands stored in the buffer is 1000, which can be upgraded to a higher number. Contact us if larger buffers are needed.

If a Stop Xbot command is received by PMC for a particular XBot, the XBot will be stopped and all buffer commands will be cleared.

If an XBot enters the Obstacle Detected state, its motion buffer will not be cleared. Once the obstacle is cleared, the XBot will resume completing the pending commands in its motion buffer.

If an XBot enters the Stopped state, typically due to it being unable to resume its previous motion, its motion buffer will be cleared. This usually occurs when an XBot enters an obstacle during Trajectory or Stream motions.

Each XBot motion command buffer status can be checked from the command label in XBot status, indicating which motion command the XBot is running.