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Screens : 

 

The unit displays 32 characters from the PLC memory.   
These characters are taken from the PLC data registers.   
 
The unit tracks register DM0020 ( the Offset register ) in the PLC.  The number in DM0020 gives 
the start address of the data register block which contains the characters to be displayed.  For 
example, if DM0020 has number 124 in it, the unit will read 16 registers from DM0124, i.e. from 
DM0124 to DM0139 and display the corresponding characters.   
 
Each register contains two bytes.  Each ASCII character to be displayed is one byte.   So, each 
word contains two characters that can be displayed.  All the PLC ladder logic has to do is to put 
the correct words in the registers being read by the unit so that a proper screen can be displayed. 
 
As mentioned above, the starting address of the screen data block is controlled by the Offset 
register, i.e. DM0020.  Hence, there can be two methods of changing the screen to be displayed.  
One is to keep the value in DM0020 constant and change the data in the screen registers in the 
ladder logic.  Second is to keep the screen text in the data memory (by editing DM registers) and 
change the value in DM0020 so as to point to the correct memory address to display the desired 
screen. 
 
It is possible to embed registers in the screens.  The unit reads 16 registers from DM0000 to 
DM0015 (in which DM0012 to DM0015 are used for Bar Graph) in every scan.  The data in these 
registers can be embedded in the screens.  To do so, use hex bytes 0 to B (C to F used for Bar 
Graph) corresponding to register DM0000 to DM0011 respectively in the screen.  Refer to the 
example given which explains the embedding of registers.  
It is possible to embed one data entry field in screens.  It is similar to embedding register, only 
instead of 0 to F use 10 to 1F hex bytes to address DM0000 to DM0015.  The registers DM0000 
to DM0015 can be  edited with this feature one at a time in a screen. 

Summary of Contents for NT2S-SF123B-E -

Page 1: ...iting this document It is assumed that the user is well acquainted with the PLC being used and with Windows based software usage in general Hereafter in the manual NT2S SF123B E will be referred to as...

Page 2: ...I0201 00 to I0201 05 Every time a key is pressed the corresponding bit as shown in the table below is held on while the key is pressed The keys also have alternate functions Key Work Register mode fu...

Page 3: ...isplay ASCII text see section on Screens for more details on this if I0200 08 and I0200 09 are OFF To allow operators to view and edit the registers I0200 09 is to be kept ON If I0200 09 is OFF the un...

Page 4: ...DM0020 Hence there can be two methods of changing the screen to be displayed One is to keep the value in DM0020 constant and change the data in the screen registers in the ladder logic Second is to k...

Page 5: ...r pump is on To display this screen do the following a Move number 200 in DM0020 since the screen text will be stored in DM0200 onwards b Move character string Last Rinse Cycle into 8 words from DM020...

Page 6: ...ex Word ASCII Hex DM0200 La 4C61H DM0208 Wa 5761H DM0201 st 7374H DM0209 te 7465H DM0202 R 2052H DM0210 r 7220H DM0203 in 696EH DM0211 pu 7075H DM0204 se 7365H DM0212 mp 6D70H DM0205 C 2043H DM0213 i...

Page 7: ...s available in data word DM0100 and the oven status is given by bit I001 00 To display the above screen do the following a Move number 200 in DM0020 since the screen will be stored in DM0200 onwards b...

Page 8: ...nd DM0214 The NT2S C will read data in DM0003 and embed in xx x format g Move s into DM0215 This command completes the screen by appending the s to the bake time This will put the following data in th...

Page 9: ...key It is advisable to create a password screen which can block the usage of the register mode Bar Graph NT2S C uses DM0012 to DM0015 registers to hold bar graph values to be displayed If Offset regi...

Page 10: ...most applications involving simple digital controls are not used anyway and simply change the offset register to display different screens The user can fill the data memory using the data display edit...

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