C Control The I Unit-M Advanced 5 Vdc Inputs / outputs 16 x digital I/Os / 8 x analogue or digital I/Os Program memory 2 198805 Datenbogen

Interface and the ports can not be used freely any more. 
 

Any usage of the RF Functions (see chapter RF OBJECT) will occupy this ports to work as special coded RF  
Interface and the ports can not be used freely any more. 
 
 

 
The Extended Ports are not really property of the Unit M 2.0 but they are treated this way by the Operating 
System. Therefore a connected IIC-Bus PCF8574 Digital Ports circuit can be accessed in the same simple 
way as the standard ports. See Chapter INSTRUCTION AND KEYWORDS for informations on read and 
write a port.  

 

 
 
 
 
 

You can use the Extended Ports if a PCF8574 is connected to the IIC-BUS. For this case you may not use 
the IIC-BUS Object, because the PCF8574 is fully supported by the Operating System This integrated circuit 
provides you 8 I/O Ports. The port index (or port number) depends on the address given to the PCF8574  
The address consists of a 4 bit fixed and 3 bit user selectable address space. The LSB defines as for I²C-
Bus devices usual the read/write action. Removing a jumper will cause the corrsponding address bit to be HI. 

 

 

 
 
 
 

READ- Operation, LSB HI                                               WRITE- Operation, LSB LO 
The table shows the relation between address and port assignment 

  

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 Using the IIC-BUS the LCD always has to be initialised even it is not used: 
 LCD.INIT 
 LCD.OFF