LB Booster - Using modem control outputs to drive a relay

LB Booster

Programming

BASIC code examples (Moderator: Richard Russell)

Using modem control outputs to drive a relay

« Previous Topic | Next Topic »

Pages: 1

Author

Topic: Using modem control outputs to drive a relay (Read 61 times)

Richard Russell
Administrator

member is offline

Posts: 1348

Using modem control outputs to drive a relay
« Thread started on: Dec 15^th, 2017, 3:54pm »

In response to a query at the LB Yahoo! group, here's a simple program to demonstrate driving the DTR and RTS Modem Control outputs from a standard serial port (internal or USB serial adaptor). On a DB9 connector DTR is on pin 4 and RTS is on pin 7. The code as shown is LBB-specific:

Code:

    ' change COM port number to suit
    open "com3:9600,n,8,1" for random as #com
    hcom = hwnd(#com)
    button #w, " Set DTR ", [setdtr], UL, 20, 20
    button #w, "Clear DTR", [clrdtr], UL, 20, 60
    button #w, " Set RTS ", [setrts], UL, 20, 100
    button #w, "Clear RTS", [clrrts], UL, 20, 140
    open "Modem Control test" for window as #w
    #w "trapclose [quit]"
    wait
    
[setdtr]
    calldll #kernel32, "EscapeCommFunction", hcom as ulong, _SETDTR as long, r as void
    wait

[clrdtr]
    calldll #kernel32, "EscapeCommFunction", hcom as ulong, _CLRDTR as long, r as void
    wait

[setrts]
    calldll #kernel32, "EscapeCommFunction", hcom as ulong, _SETRTS as long, r as void
    wait

[clrrts]
    calldll #kernel32, "EscapeCommFunction", hcom as ulong, _CLRRTS as long, r as void
    wait

[quit]
    close #com
    close #w
    end

Richard.

Logged

Pages: 1


« Previous Topic \| Next Topic »