User`s guide

Section 2 — Software Set-Up Bulletin No. VVDED397053US

Interbus-S Protocol November 2000

Exchanges via Message Handling

The maximum message length is 128 bytes. Message handling services

conform to the Peripheral Communication Protocol (PCP) standard for

communication services. This is without an error check.

In order to send messages to both output periodic words (6040h and

6042h) ProcDatEnab must be set to zero. This disables the periodic data

exchange. If the periodic data exchange is not disabled the next periodic

data exchange overwrites the message data.

NOTE: All messages pass through all of the slaves on the network, but

slave-to-slave communication is not possible.

The variables exchanged via message handling are described in the

ATV58 Register Access Guide for Communication Networks,

VVDED397058US. To command and control the speed of the drive

controller, the command variables in Tables 14 (page 23) and 15

(page 26) must be used. Interbus-S protocol assigns the control register

and the speed setpoint to the output periodic words by default. Message

handling must therefore not be used to transmit these commands, as they

will be immediately replaced by the next exchange of periodics.

Accessible Data

The two following types of objects can be accessed:

• User objects (Index 0x5FE0 to 0x5FFF)

• Drivecom objects (Index 0x6000 to 0x6049)

Control and Supervision

Interbus-S protocol is used to control exchanges.

If an invalid message is sent to the slave device, it transmits an exception

response to the master device. The master then decides whether to

repeat the exchange or not.

Table 7: Periodic Exchange Parameters

Periodic Type Index Meaning

Input

0x6041

0x6044

Status word (StatusWord)

Motor speed (SpeedActValue)

Output

0x6040

0x6042

Control word (ControlWord)

Speed reference (SpeedSetP)

VVDED397053USBook Page 18 Tuesday, November 28, 2000 9:01 AM