Mitsubishi Electric F930GOT-BWD-E, Руководство пользователя

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Graphic Operation Terminal F930GOT Introduction 1
1-29
• Communication procedure
In communication between the GOT and the host unit, the host unit sends a command, and
the GOT sends back a response. While the GOT is sending the response to the host unit,
the GOT cannot receive new commands from the host unit.
When an error occurs, the GOT sends back a NAK code as a response. The contents of the
error can be checked by reading a special memory.
As an exception, when a notification of interrupt from the GOT is given, the GOT sends an
interrupt code. However, while sending a response, the GOT does not send an interrupt
code. In such a case, immediately after sending a response, the GOT sends an interrupt
code. The GOT may send an interrupt code while receiving a command.
When an event such as change in the ON/OFF status of a specific bit and screen
changeover has occurred, the GOT sends an interrupt code. The table below shows the
correspondence between the interrupt code and the event type.
Table 1.16:
Event type Interrupt code (hexadecimal)
M8000 is changed to ON.
M8000 is changed to OFF. 50
51
M8001 is changed to ON.
M8001 is changed to OFF. 52
53
žžž
M8023 is changed to ON.
M8023 is changed to OFF. 7E
7F
žžž
M8049 is changed to ON.
M8049 is changed to OFF. B2
B3
Display screen is changed over. 20
Input of a numeric is completed. 21
Transfer of a data file is completed. 22
Host unit
GOT
Command
Response
Command
Response
Command
Response
Host unit
GOT
Interrupt