Communications

To move applications from one computer to another, first determine if the two computers have compatible media. For example, if they can read each other's floppy disks or tapes, run BXSND on one machine to create the transfer file, move that file to the other machine, and run BXRCV using that file. If no such capability exists, consider going port-to-port.

Because there is not a real standard for communications, BXSND/BXRCV is designed with minimal expectations. The following is the communication environment expected by BXSND/BXRCV:

Two-way communications are needed.

Digits 0..9, letters A..Z, and "<" and ">" must be transmittable.

The sending machine must not add any additional data to the transmission (such as a linefeed after every 80 characters) that will be read by BXRCV on the receiving machine.

The RECEIVING machine may transmit XON and XOFF without undesired effects.

Single-character communications must be possible both ways. In other words, if one program transmits a single character the other program may instantly read that character. This is also known as unbuffered data communications or RAW mode.

The SENDING machine does not require any input buffering.

The RECEIVING machine requires at least one-character input buffering.

Modification of the high bit during transmission is OK.

There must be NO echo on either port.

The sending BASIC must provide a communications port name as well as TIM= option when reading from the port name.

The sending BASIC must provide a compatible LRC() function.

To test communications, enter the following program in one BASIC:

0010 OPEN(1)"your port name"
0020 READ RECORD(1,SIZ=1,TIM=200)A$
0030 PRINT HTA(A$),
0040 GOTO 0020

If the sending BASIC will not accept this program, communications will not be possible with this utility. In the other BASIC enter the following lines in console mode:

>OPEN(1)"your port name"
-- start up the other program now --
>PRINT(1)"A",
>PRINT(1)"TEST",
…

Ensure each PRINT ends with a comma. After each PRINT, check for HEX values being received by the other program. There should be no delay in receiving data. Try several different PRINT statements. If everything works, perform the same test with the machines reversed. Remember, the SENDING machine does not need to receive more than one character at a time. If the desired results do not occur, check your owner's manual or call whoever supports your machine for technical assistance. A cabling problem or a problem with the communication drivers on a particular machine may be the cause. On the UNIX operating system, or on a XENIX system, an stty command may be necessary to place a port in the proper modes. Also make sure the parity modes and baud rates match between the two machines.