Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 224

6 PROGRAMMING
No.
SB0020 Module status
No.
SB008D Module type of each station
No.
SB0042 Power supply status of host
SB008C External power supply information
No.
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(14) Checking the communication status between the network module
and CPU module
The communication status between the network module and CPU module can be
checked by using the link special relay (SB) or link special register (SW).
(a) Checking the error details
1) When an error occurs during the communications between the
network module and CPU module, Module status (SB0020) is turned
ON.
2) An error code is stored in Module status (SW0020).
Description
(b) Checking the module type
The module type data are stored in the following link special relays (SB)
and link special registers (SW).
Description
(c) Checking the external power supply status
1) When external power is supplied, External power supply information
(SB008C) is turned ON.
The status of the host can be also checked with Power supply status
of host (SB0042).
2) Station numbers of the stations to which external power is supplied
are stored in Power supply status of each station (SW008C to
SW008F).
Description
(d) Checking the current communication speed
When the twisted bus system is configured, current communication speed
is stored in the following special register (SW).
Description
No.
SW0020 Module status
No.
SW00E8 to
Module type of each station
SW00EB
No.
SW008C to
Power supply status of each station
SW008F
No.
SW006A
Current communication speed value
MELSEC-Q
Description
Description
Description
Description
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