Siemens SPC3 Especificaciones descargar pdf (Pagina 22)

Introduction To ProfiBus DP

__________________________________________________________________

_______________________________________________________________________________________

Acromag, Inc. Tel:248-624-1541 Fax:248-624-9234 Email:sales@acromag.com http://www.acromag.com

The address stored in EEPROM can only be modified via the

Set_Slave_Address command. Additional changes to the internal EEPROM

address can also be locked out. If the internal EEPROM address is also set

to 126 (and the external switches are at 126), then the unit will await the

Set_Slave_Address command to change its EEPROM address to a valid

address from 0-125, before proceeding to the parameterization state. Note

that if the address lock bit has been set (locked), then further changes via

Set_Slave_Address are effectively locked out. In this case, you may set the

external switches to 255 (FFH) and re-power the unit, this will clear the lock

bit and restore the internal EEPROM address to 126.

Set_Slave_Add Telegram (SAP 55)

Before commissioning, a station must have already been assigned a

unique station address from 0-125. This is usually accomplished via

hardware switches on the device. In the event that the device does not

provide switches for setting its address (or its address switches are set to

126), the address can be set via this bus command from a class 2 master.

The Set_Slave_Add telegram is used by a class 2 master to change a

slave’s address following power-up when its address cannot otherwise be

set via hardware switches (and it has a default address of 126). This

command also allows further address changes over the bus to be locked

out. Note that this telegram transmits the Ident_Number for security

reasons. If the ident_number does not match that of the targeted slave, the

address will not be changed. Additionally, if the lock bit has already been

set, then again, the address will not be changed.

DP slaves that have not been assigned an address typically have a

default address of 126, which is reserved for commissioning via class 2

master devices. No class 1 master is allowed to use address 126 to

communicate. Further, only one slave with address 126 is permitted to be

connected to the network at one time and this address may not be used to

exchange I/O data.

With respect to Acromag modules which support address changes via

external switches and optionally via this command, the Set_Slave_Address

command is used to modify the internal (EEPROM) address setting. The

internal address setting will determine the slave address if the unit is

powered-up with the external switches set to 126. Otherwise, if the external

switches are set from 0-125, then the switch settings determine the slave

address, not the value stored in EEPROM. However, in order for the

Set_Slave_Address command to change the slave address, both the internal

EEPROM address and external switches must be set to address 126 prior to

power-up. The Set-Slave_Address command will be rejected with the RS

error code for any other conditions.

Set_Slave_Add Telegram

SD LE LEr SD DA SA FC DSAP SSAP DU FCS ED

68H 09H 09H 68H XX XX X 37H

(55)

3EH

(62)

X.. X 16H

1 2 ... 17 18 19 20 21 22 23 24 25 26 27 ... 37 38

Comentarios a estos manuales

Sin comentarios

Siemens SPC3 Especificaciones Pagina 22

Comentarios a estos manuales

Relacionado con productos y manuales para Redes Siemens SPC3