Parker Hannifin GEM6K manual Varsho, Shared Output Variable for Peer-to-Peer Data Exchange

;**** This code is executed on unit #2: **************************
NTID2	; Set unit ID to 2
NTRATE100	; Set the sharing rate to 100ms and enable this unit
VAR1=1VARSHI1	; Load the value of unit #1's first shared data (1PE) into VAR1
WRITE"AXIS 1 AT POSITION" ; Report axis 1's current position (the value of VAR1)
WRVAR1	; Calculate offset position: Subtract synch unit #3's
VAR2=8PCEA-3VARSHI2
	; VARSHO2 (4PCEA) from the captured encoder position
IF(VAR2>10000)	; of axis #8 (8PCEA).
	; If position offset by more than 10000 encoder counts
WRITE"AXIS 20 OUT OF POSITION"
NIF	; Get unit 3's VARSHO1 information (3AS)
VARB1=3VARSHI1
IF(VARB1=B1)	; If axis 3 on unit #3 (axis #19) is in motion
WRITE"AXIS 19 IN MOTION"
NIF
;*************************************************************************

VARSHO		Shared Output Variable for Peer-to-Peer Data Exchange
Type:	Variable; Network		Product	Rev
Syntax:	<!>VARSHO<i><=xx>		6K	5.3
Units:	i = variable number

xx= 32-bit data operand (see list below)

Range: i = 1-8

Default: n/a

Response: VARSHO1: *VARSHO1=PME

See Also: NTRATE, VAR, VARB, VARI, VARSHI

The VARSHO command is used to set up data to be shared over a peer-to-peer Ethernet connection (i.e., connection between other 6K or Gem6K products).

Each unit on the Ethernet peer-to-peer network has eight “shared output” variables (VARSHO1 through VARSHO8) with which it can share with other units the values of its motion attributes, controller status, variables, etc. (see list below). The type of data can be either binary, as in the AS (axis status) operand, or a 32-bit unscaled integer, as in PE (encoder position) operand. The data stored in the VARSHO is not scaled.

For example, unit #2 could execute VARSHO1=3PE to share the encoder position of axis #3 in shared output variable #1.

Each unit will re-broadcast its updated VARSHO data at a rate set with the NTRATE command. RECOMMENDATION: Set all devices to broadcast at the same NTRATE rate of 50 milliseconds.

The Implementation Process, beginning on page 8, identifies how to use the VARSHO command in context with the process of setting up the peer-to-peer Ethernet data sharing.

Options for shared data in the VARSHO variable:

A	Acceleration	NMCY ...	Master cycle number	SS	System status
AD	Deceleration	OUT	Output status	SWAP	Task swap assignment
ANI	Analog input voltage	PANI ...	Analog input position	TASK	Task number
ANO	Analog output voltage	PC	Commanded position	TIM	Timer value
AS	Axis status	PCC	Captured command pos.	TRIG	Trigger interrupt status
ASX	Extended axis status	PCE	Captured encoder pos.	US	User-defined status
D	Distance	PCME ...	Captured master enc. pos.	V	Velocity
DAC	DAC output value	PE	Encoder position	VARI	Integer variable
DKEY ...	RP240 keypad value	PER	Position error	VARB	Binary variable
ER	Error status	PMAS ...	Position of Master	VEL	Commanded velocity
FB	Feedback device pos.	PME	Master encoder pos.	VELA	Actual velocity
FS	Following status	PSHF ...	Net position shift	VMAS	Velocity of the master
IN	Input status	PSLV ...	Follower pos. command	VARSHI.Shared input variable
INO	Enable input status	SC	Controller status
LIM	Limit input status	SCAN ...	PLC scan time
MOV	Axis moving status	SEG	Free segment buffers

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