User`s manual

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CHAPTER 1 OVERVIEW
1
1.1 Overview
(c) When a remote password is set in the QCPU with the GX Developer, the following
access from the external device to QCPU using the Q series C24 modem function
can be performed by executing the unlock processing to the remote password.
*1
• Data communication using the MC protocol
• Accessing the programmable controller using the GX Developer
*1 The remote password function is a QCPU function designed to prevent improper access to the QCPU by users. The
QCPU remote password function can be used by setting a remote password in the QCPU with GX Developer.
(3) Receiving data with an interrupt program ( Page 184, CHAPTER 4)
(a) In data communication between the Q series C24 and the external device, an
interrupt program can be used to receive data for the following data communication
functions.
• Data reception during communication using the non procedure protocol
• Data reception during communication using the bidirectional protocol
(b) Receiving data using an interrupt program expedites data reception by the
programmable controller CPU.
*1
RS-232
Modem/TA
(*1)
Modem/TA
(*1)
External device
Pager receiver
Q series C24
TA is an abbreviation for Terminal Adapter.
BUFRCVS
SM400
FEND
I
Main program
Interrupt
program executed
Main program
Receive
Q series C24
Interrupt issued
Data
transmission
Programmable
controller CPU