Chapter 3 Creating and Editing Screens   
 
Fig. 3-4-5 Curve Elements on HMI Screen 
  Curve Clear Flag 
Bits 8 to 11 (flags 1 to 4) clear the curve (Trend Graph, X-Y Chart, X-Y distribution or 
Curve Input) when this flag is turned ON (For more details on the settings of curve 
element, please refer to section 3.8.10). To control the curve clear flag again, this flag 
must be turned OFF and then ON again. 
For example (refer to Table 3-4-1 and Fig. 3-4-5), if D2 is set to 512 or $17.9 is set to 
1, the curves of figure 3 will be cleared and the curves of figure 1, 2 and 4 will not. 
When D2=512, it indicates that Bit 9 of D2 is 1(0000 0010 0000 0000). 
 
Sampling History Buffer Register (HBSR) 
Delta DOP-B series has 12 Bits that control the sampling address of history buffer (refer to 
Fig. 3-4-6 and the following table). Not only Timer, the history buffer can be controlled by 
a PLC if the Trigger Source in the History Buffer setup is set to a PLC from Timer. For more 
details on History Buffer setup, please refer to section 3.11.3. 
Corresponding Flag 
Corresponding 
Buffer Area 
Bit 
Binary Display of Relative 
Position (x) 
Function 
Buffer Area 1  0  0000 0000 0000 000x  Sampling History Buffer 1 
Buffer Area 2  1  0000 0000 0000 00x0  Sampling History Buffer 2 
Buffer Area 3  2  0000 0000 0000 0x00  Sampling History Buffer 3 
3-30  Revision May, 2010