Athena C10 line Manual de Instruções descarregar pdf (Página 15)

Example: Error code in response to the request indicated above.

ADDR

FUNC

DATA

Except.

Code

CRC

0A 81 02 B0 53

4.1 Error Codes

Although the MODBUS standard uses 8 error codes, the ATHENA

CONTROLS implementation of the protocol uses only four:

Code Name Meaning

ILLEGAL FUNCTION

The function code received does not correspond

to a function allowed on the addressed slave.

ILLEGAL DATA

ADDRESS

The address to which the data field refers is not

an address allowed on the addressed slave.

ILLEGAL DATA VALUE

The value to be assigned, specified in the data

field, is not allowed for this address.

NAK - NEGATIVE

ACKNOWLEDGMENT

The function cannot be performed under the

current operating conditions or an attempt has

been made to write in a read-only address.

5. MODBUS ON ATHENA CONTROLS PLATINUM® INSTRUMENTS

5.1 Serial communications parameters

The parameters are shown in the below table:

Parameter Parameter

code

Set up range

Communications protocol

Prot MbuS / JbuS

Serial address

Addr 1 ... 247

Baud rate

baudr 1200, 2400, 4800, 9600, 19200

The protocol is chosen by means the M.buS o JbuS selection.

The address can be set among 1..247 and must be unique for each

instrument connected on the same line.

The Baud rate parameter enable a clear and simple communications

speed setting.

No Parity and stop bit must be set. They have already been set by the

manufacturer as follows:

Parity = none

Stop bit = 1

5.2 Communications time

The messages, as described in Chapter 2.4, must be exchanged with an

internal pause that is less than 3 times the time required for a character

to be exchanged, otherwise it would be interpreted as the end of the

message. The ATHENA CONTROLS instruments with the MODBUS

protocol are able to receive and transmit characters without an interval.

Between a master message and the following reply on the part of the

instrument there is a latent time lapse necessary for the completion of the

function. This is connected to the fact that, once a command has been

received, the instrument responds only after having completed the

1 2 ... 10 11 12 13 14 15 16 17 18 19 20 ... 106 107

Comentários a estes Manuais

Sem comentários

Athena C10 line Manual de Instruções Página 15

Comentários a estes Manuais

Manuais e produtos relacionados com não Athena C10 line