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Siemens AG
Entry type: Product note Entry ID: 4126252, Entry date: 08/27/1996

S5-115U, CPU 944B - New Revision Level A06

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  • Associated product(s)


Concerns products with the Catalog Nos.:                                    


6ES5 944-7UB11   CPU 944B, 96 Kbyte, 1 serial port                          

6ES5 944-7UB21   CPU 944B, 96 Kbyte, 2 serial ports                         




_Reason for the change:_                                                    


Modules with revision level A05 manufactured in the period May              

to Nov. 1995 may enter STOP mode with QVZ (acknowledgement                  

delay) due to wrong address accessing, in sporadic cases.                   


The problem is restricted to modules that are accessed via the              

intelligent I/O / absolute address area (0000H to 0FFFH), or                

via page addresses (F400H to F7FFH).                                        


Affected modules have the following manufacturing stamps:                   


C-F5..., C-F6..., C-F7..., C-F8..., C-F9..., C-F0..., C-FN...,              




If the problem occurs with any of your modules please speak                 

to your SIMATIC contact at your local Siemens office about an               





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