Transition bits for counters are stored within the locating reference. 1 GFK-0402G Chapter 1 Introduction to the Hand-Held Programmer 1-5 In the Series 90-30 model 331, 340, 341, and 351 CPU, override bits can be set. When override bits are set, the associated references cannot be changed from the program or the input device; they can only be changed on command from the programmer. Neither the Series 90-30 model 311 or 313 CPU nor the Series 90-20 model 211 CPU supports overriding discrete references. Retentiveness of Data Data is said to be retentive if it is saved by the PLC when the PLC is stopped. Unless otherwise stated for a particular model of CPU, the Series 90 PLCs preserve program logic, fault tables and diagnostics, overrides and output forces, word data (%R, %AI, %AQ), bit data (%I, %S (%SC is retentive: not %SA or %SB), %G, fault bits and reserved bits), %Q and %M data (unless used with non-retentive coils), and word data stored in %Q and %M. %T data is not saved. %Q and %M references are non-retentive (that is, cleared at power-up when the PLC switches from STOP to RUN) whenever they are used with non-retentive coils. Non-retentive coils include coils -( )-, negated coils -( / )-, SET coils -( S )-, and RESET coils -( R )-. When %Q or %M references are used with retentive coils, or are used as function block outputs, the contents are retained through power loss and RUN-to-STOP-to-RUN transitions. Retentive coils include retentive coils -( M )-, negated retentive coils -(/M)-, retentive SET coils -(SM)-, and retentive RESET coils -(RM)-. The last use of a %Q or %M reference on a coil instruction determines its retentive state.
Warning: include_once(/js/tracking.php): failed to open stream: No such file or directory in /var/www/series/revision.php on line 248
Warning: include_once(): Failed opening '/js/tracking.php' for inclusion (include_path='.:/usr/share/php:/usr/share/pear') in /var/www/series/revision.php on line 248