ST Examples

Every channel in IO Mapping is exposed as a global variable through its DefaultMapping name: IN0–IN6, OUT0–OUT5, AN0–AN2 and LED are usable directly, with no declaration and no mapping.

Blink the RGB LED red

LED is a DWORD in 0x00RRGGBB form, not a bit:

PROGRAM PLC_PRG
VAR
    blinker : TON;
    xOn     : BOOL;
END_VAR

blinker(IN := NOT blinker.Q, PT := T#500ms);
IF blinker.Q THEN
    xOn := NOT xOn;
    IF xOn THEN
        LED := 16#00FF0000;     // red
    ELSE
        LED := 0;               // off
    END_IF
END_IF

Full brightness is harsh at close range; 16#00200000 is plenty for an indicator.

Colour by state

PROGRAM PLC_PRG
IF xFault THEN
    LED := 16#00FF0000;         // red
ELSIF xConnected THEN
    LED := 16#0000FF00;         // green
ELSE
    LED := 16#00FFA000;         // amber: running, not connected
END_IF

Digital pass-through

PROGRAM PLC_PRG
OUT0 := IN0;
OUT1 := IN1;
OUT2 := IN2;
OUT3 := IN3;
OUT4 := IN4;
OUT5 := IN5;

Analog threshold

PROGRAM PLC_PRG
OUT0 := AN0 > 2048;             // raw 12-bit count, 0...4095 over 0...3.3 V

There is no TEMPERATURE channel on this board — see IO Mapping.

Ask the modem its status

The complete pattern, including the GVL with the located variables, is on the Modem page:

CASE nStep OF
0:  GVL.sOut  := 'AT+CFUN?';
    GVL.wSend := 1;
    nStep := 1;
1:  GVL.wSend := 0;
    nStep := 2;
2:  IF GVL.wInLen > 0 THEN
        sResp := GVL.sIn;       // e.g. '+CFUN: 4' then 'OK'
        nStep := 3;
    END_IF
END_CASE