Developers Area - DOS API

The RCI API, is a very simple way for accessing the Hardware board (RCI). The way it works is quit similar to the way other interfaces, like BPQ for communications applications, or KCT to handle other Rotators systems, works. To begin using this software interface, you have to load first of all, the RCIPlus.EXE driver. Remember: You must have, at least, in the same directory, the file RCIPLUS.CNF. To set this configuration file, you'll use the Setup.exe program. You will access the RCI driver through the INT 61H (97 decimal). There are 6 functions available, the method employed to use them is call the Int 61H and passes the function value in AH.
List of functions available:

1) Initialize the Interface (AH=0).-

• Input Registers:
  • AH=0 Init the interface
  • DX=LPT Port

If LPT=0 (DX=0), it means the Lpt will use the interrupt value set in the ARS.CNF file. In the case you want use different value, i.e. 278H, set DH=02H and DL=78H or DX=0278H

• Output Register:
  • AX=RET Always on AX, it will return the Return value.

RET=0 OK, initialized successfully.
RET!=0 Hardware problem (i.e. cable not connected, RCI is turned off, or Board Problem)

• Meaning:

  This function is always the first one to be used. If this function is not used, or if the RET value <> 0, the other functions will not be available to the programmer. Normaly DX will be equal to 0. So verify that the RCIPLUS.CNF is correctly configured.
  If RET = 0 a timer-tick subrouting is installed, wich dies when the stop function is called.

2) Solenoid Relay activation (AH = 1).-

• Input Registers:
  • AH=1 Relay activation
  • DH=Action Value

=00H Stop all Relays
=01H Brake release (Central Relay-K2 on RCI Board)
=02H Left Relay activation
=04H Right Relay activation

=16H Up Relay activation
=32H Down Relay activation

• DL= Azimuth/Elevation Rotor

=00H Azimut Rotor
=01H Elevation Rotor

• Output Register:
  • AX=RET Ret = Relays' status

    RET=0 All relays stopped
    RET=1 Brake Relay activated
    RET=2 Left Relay activated
    RET=4 Right Relay activated
    RET=16 Up Relay activated
    RET=32 Down Relay activated
    RET=FFFFH Error returned (i.e. Init failed)

• Meaning:

  This function is used only if it's desired activating the relays manualy. Normally, the AH=4 function will be used in typical applications (Turn to a point function).

3) Read Antenna Position (AH = 2).-

• Input Registers:
  • AH=2 Read Antenna Position
  • AL=Mode Mode maybe a Degrees value(0-360) or a Digital value (0-255).

    =0 Return the value in Degrees
    =1 Return the A/D value.

    DH=Sampling number (1-255)

  • DL=Azimuth/Elevation

    =0 Use the Azimuth input (J3).
    =1 Use the Elevation input (J4).

• Output Register:
  • AX=RET Ret = Position value

    It will be in the range 0-360 for Degree values(AL=0), or of 0-255 for Digital values (AL=1)
    RET=FFFFH Error returned. Normally because Init failed.

• Meaning:

  This function is usefull to know the antenna direction. Normally it will be used with Mode=0 (Degree) but it maybe necessary to know the A/D value for any kind of reason, so use AL=1.
  The DH register, the sampling number, is used to average the value read. It works on the following way: If DH=9 the RCI Driver will read 9 times the value, and it will average the result. With this feature, any minimum movements caused by the wind, etc. will be discarded

4) RCI board Status (AH = 3).-

• Input Register:
  • AH=3 Status

• Output Register:
  • AX=RET Ret = Relays' Status

    RET=0 All relays stopped
    RET=1 Brake Relay activated
    RET=2 Left Relay activated
    RET=4 Right Relay activated
    RET=16 Up Relay activated
    RET=32 Down Relay activated
    RET=FFFFH Error returned. Normally because Init failed.

• Meaning:

  This function returns the relays' Status.

5) Turn the rotator to a specific Point (AH = 4).-

• Input Registers:
  • AH=4 Turn to a Point (Degrees only)
  • AL= Azimuth/Elevation

    =0 Use the Azimuth rotor
    =1 Use the Elevation rotor

  • DX=Value. The value will range between 0-360 i.e. to turn to 300 degrees, set DH=01H and DL=2CH

• Output Register:
  • AX=RET Return the result

    RET=0 Command accepted
    RET=FFFFH Error returned. Normally because Init failed.

• Meaning:

  This function is used to turn the antenna to a desired point. The value of the point must be in Degrees (0-360).

6) Stop using the interface (AH = 5).-

• Input Register:
  • AH=5 Stop using the Interface.

• Output Register:
  • AX=RET Return the result

    RET=0 Command accepted
    RET=FFFFH Error returned. Normally because Init failed.

• Meaning:

  This function notifies to the RCI driver to Stop using the interface. It also stops the timer-tick subroutine. After using this function, the only function available is the Init function.

You can view a sample program in "C" language.