Eurotherm 7000 Series, Руководство пользователя

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Digital Communication
7300A User Manual 6-4
6.2.3. ADDRESSING BY MESSAGE BROADCASTING
00 address is reserved for the message diffusion to all the units connected to the bus.
In this case, all the Slaves carry out the order but none will answer.
Writing diffusion is available on every parameters with the ‘Read and Write’ status.
Important !
User is responsible for ensuring that a write command broadcast does not
affect the operation of other units on the same communication bus.
In a program loop, the Writing of a parameter which is saved in permanent
memory must not be included
6.3. DIAGNOSTIC LED
S
Three LEDs on the front panel show the interface status
!
Important :
If 00 address (reserved for broadcast) is selected by mistake, the interface remains in the
initialisation phase
Orange ‘Rx’ LED
Linked to data received, and flashes as requests are sent by the master.
Important :
If the ‘Rx’ LED is lit steadily, the polarity of the communication signals may be inverted
Orange ‘Tx’ LED
linked to data sent, and flashes as responses are sent by the Slave.
Initialisation phase Waiting for Communication
on power up frame Master
established
Flashes 5 times : Flashes at Lit standily
400 ms on - @ 0.5 Hz
400 ms off
1 s on / 1 s off
Green ‘ON/Dxch’ diagnostic LED
ON/
Dxch
Rx
Tx
Orange LED -
Communication bus transmission
Green LED -
supply and date exchange
Orange LED -
Communication bus reception
Figure 6-2 Interface status diagnostic LEDs Table 6-1 operation of green ‘ON/Dxch’ LED
6.4. ERROR CODES
If the interface detects an error in the frame received, it returns an error code :
Error Code Error type
(decimal)
1 Prohibited function
2 Prohibited parameter address (unauthorised code sent)
3 Internal link failure (if present)
4 Prohibited data value
9 No data in request
10 Too much data in request
Table 6-2 Meaning of communication error codes