Function Blocks 
Function block listings 
8    HC900 Hybrid Control Designer Function Block Reference Guide  Revision 11 
  2/07 
Function Block Type Identification Label  See Page 
TAHD  (Track and Hold) 
H382 
TCPR  (Modbus/TCP Read) 
H384 
TCPS  (Modbus/TCP Slave) 
H388 
TCPW  (Modbus/TCP Write) 
H396 
TGFF  (Toggle Flip Flop) 
H384 
TMDT  (Time and Date) 
H402 
TOT (Totalizer) 
H403 
TPO  (Time Proportional Output) 
H406 
TPSC  (Three Position Step Control) 
H409 
TRIG (Trigger)     
H424 
UPDN (UP/Down Counter) 
H426 
VLIM (Velocity (rate) Limiter) 
H428 
WCON (Write Constant) 
H430 
WTUN (Write Tuning Constants) 
H432 
WVAR (Write Variables) 
H434 
XFR (Transfer Switch)  
H436 
XOR (Exclusive OR) 
H438