Schneider Electric 4000 manual Overview of the Command Interface, 182

Appendix B—Using the Command Interface	63230-300-212
Overview of the Command Interface	April 2001

OVERVIEW OF THE COMMAND INTERFACE

The circuit monitor provides a command interface, which you can use to issue commands that perform various operations such as controlling relays. Table B– 2 on page 183 lists the available commands. The command interface is located in memory at registers 8000–8149. Table B– 1 lists the definitions for the registers.

Table B– 1: Location of the command interface

Register	Description
8000	This is the register where you write the commands.
	These are the registers where you write the parameters for a
8001–8015	command. Commands can have up to 15 parameters associated
	with them.
8017	Status pointer to the user area. The status of the last command
	processed is placed in this register.
8018	Results pointer to the user area. When an error occurs, the error
	code is placed in this register.
8019	I/O data pointer to the user area. Use this register to point to data
	buffer registers where you can send additional data or return data.
	These registers are for you (the user) to write information.
	Depending on which pointer places the information in the register,
	the register can contain status (from pointer 8017), results (from
8020–8149	pointer 8018), or data (from pointer 8019). The registers will contain
	information such as whether the function is enabled or disabled, set
	to fill and hold, start and stop times, logging intervals, and so forth.
	By default, return data will start at 8020 unless you specify
	otherwise.

When registers 8017–8019 are set to zero, no values are returned. When any or all of these registers contain a value, the value in the register “points” to a target register, which contains the status, error code, or I/O data (depending on the command) when the command is executed. Figure B–1shows how these registers work.

NOTE: You determine the register location where results will be written. Therefore, take care when assigning register values in the pointer registers; values may be corrupted when two commands use the same register.

Register 8017

8020

Register 8018

Register 8019

	Register 8020	1	(status of the
			last command)
8021
			(error code caused by
	Register 8021	51
			the last command)
8022
			(data returned by the
	Register 8022	0
			last command)

Figure B–1: Command Interface Pointer Registers

182 © 2001 Schneider Electric All Rights Reserved