Mitsubishi MELSEC L Series User Manual page 186

(2) Changing the response monitoring time (timer 1)
When changing the response monitoring time (timer 1) default value (5 s), observe
the following precautions.
(1) Data communications using an MC protocol
6 - 8
2) Data communications using bidirectional protocol
• Stores the error code to the data transmission result storage area
(buffer memory addresses 257
performs transmission processing abnormal completion.
• While waiting to transmit a response message, the Q series C24 does
not check the response monitoring time.
The response monitoring time (timer 1) is registered on the GX Configurator-SC's
"Transmission control and others system setting" screen. For data
communication using the MC protocol, set the response monitoring time so that it
is longer than the message wait time. ( 1)
1 The message wait time is designated at the following locations.
• A compatible 1C frame: Designate in a command message
• QnA compatible 2C/3C/4C frame: GX Configurator-SC "MC protocol
system setting" screen
POINT
In any of the following cases make the default value the message wait time
described in Section 6.4, or longer.
(a) When designating the monitor conditions with the following functions, set
the maximum time matched to system operation.
• Word units random read (Refer to the MELSEC-Q/L MELSEC
Communication Protocol Reference Manual.)
• Device memory monitor (Refer to the MELSEC-Q/L MELSEC
Communication Protocol Reference Manual.)
(b) Access other than (a) above
1) When accessing a station connected (including multidrop link) to an
external device, set the following value, or longer.
Response monitoring time > = Maximum number of scans required to process
2) When accessing another station over a network system, set the default
value to infinity or the following time, or longer.
Response monitoring time > = Maximum number of scans required to process
When setting the default value to infinity, check the external device
response wait time and initialize the Q series C24 transmission
sequence when time-out is generated. (Refer to the section describing
"Contents of data designation item" of each frame in the MELSEC-Q/L
MELSEC Communication Protocol Reference Manual.)
Refer to the MELSEC-Q/L MELSEC Communication Protocol Reference
Manual for the maximum number of scans and the communication time
required by processing.
6 CHANGING THE DATA COMMUNICATIONS MONITORING TIMES
, 267
H
the command used
time
the command used
) for the target interface and
H
connected station scan
communications time
6 - 8