Just BASIC Programming - TERMINAL.bas

Just BASIC Programming

JB Programming Discussions (Moderators: ShirleyMSmith, Welopez, jaba)

TERMINAL.bas

« Previous Topic | Next Topic »

Pages: 1

Author

Topic: TERMINAL.bas (Read 320 times)

Serial Comms
Guest

TERMINAL.bas
« Thread started on: Apr 28^th, 2005, 5:41pm »

I've just picked up JB and am having some fun with it. I'm going to use it for control applications through serial ports. Using TERMINAL.bas I've rigged up some code to listen to devices. The question I have is in the example code how does the Variable "Com" know which port it is buffering when you are opening multiple ports?

Logged

Cborrow
Member in Training

member is offline
Avatar

PHP Guru

Gender:

Posts: 37

Re: TERMINAL.bas
« Reply #1 on: Apr 28^th, 2005, 6:35pm »

In the terminal.bas program there are these three lines
Code:

'Open communications port 2.  It's handle is #comm.
    'If you need to change to com 1, this is the line to modify
    open "COM1:9600,n,8,1,ds0" for random as #comm

I think that all you would do is change COM1 to COM2 or COM3 depeding on the port you are looking for, but I am just taking a wild guess.

Logged

Unrelated Studios

Serial Comms
Guest

Re: TERMINAL.bas
« Reply #2 on: Apr 29^th, 2005, 3:35pm »

Sorry about not being clear. I understand how to change ports my question is regarding the input buffer "Com" (From TERMINAL.BAS:

'Set the size of the communications buffer to 16K
Com = 8192 * 2

I would have thought that each Opened device would have its own buffer. But I don't even see where a device is explicitly bound to the buffer.

Logged

Rod
Administrator

member is offline
Avatar

Graphics = Goosebumps!

Gender:

Posts: 2427

Re: TERMINAL.bas
« Reply #3 on: Apr 29^th, 2005, 4:30pm »

From the help file:-
Quote:

To set the in and out communications buffers (each port has its own), set the variable Com (notice the uppercase C) to the desired size before opening the port. Changing the variable after opening a port does not affect the size of the buffers for that port while it is open.

    'set the size of the communications buffers
    '(in and out) to 16K each
    Com = 16384

Once you set the system variable "Com" you then use "open Com1/Com2/Com3" and that opens the specified com port with its own input and output buffers of the size specified.

« Last Edit: Apr 29^th, 2005, 4:31pm by Rod »

Logged

Rod.

Got time for a game? http://www.freewebs.com/gamebin/

Pages: 1


« Previous Topic \| Next Topic »