5.11 Standard Counter Function Blocks
5.11.2 Down counter
5-199
5
APPLICATION
FUNCTIONS
CTD(_E)
CTD(_E)
Operation Error
No operation error occurs in the execution of the CTD (_E) function.
Program Example
The program which counts the number of times that bit type data input to is turned from OFF
to ON, and turns ON when the value of reaches 0.
(a) Function without EN/ENO (CTD)
[Structured ladder]
[ST]
CTD_Inst ( g_bool1, g_bool2, g_int1, g_bool3, g_int2 );
(b) Function with EN/ENO (CTD_E)
[Structured ladder]
[ST]
CTD_E_Inst ( g_bool1, g_bool2, g_int1, g_bool3, g_int2)
s1
d1
d2