Amos Professional Manual  Contents  Index

Accessing a Printer

AMOS Professional offers total access to the Amiga's printer driver. The printer configuration is taken directly from your Preferences settings, allowing printer control with a standard set of "escape codes".

Any AMOS Professional screen can also be dumped directly onto paper via your printer.

The printer device
Details of your printer are taken from the settings that have been previously entered from the Workbench Preferences utility. A printer can be connected to the Serial Port or the Parallel Port, mid AMOS Professional will choose the appropriate device for all printing operations automatically.

The first time that a printer is used, the printer drivers are loaded into memory from your start- up disc. If this is not available, a requester will be displayed enabling you to insert the relevant disc.

The printer driver consumes a great deal Of memory, and can require up to 50k in order to operate. If available memory is running short, it may be easier to access the printer with the SERIAL or PARALLEL commands instead. Additionally, if multi-tasking is being used, it is important to realise that only one program is allowed to access the printer device at any one time. If a previous program has already grabbed the printer, an error message will be generated when an attempt is made to access the printer from an AMOS Professional program.

Such errors can be trapped using a command like this:

X> Trap Printer Open
   If ERRTRAP : Print "Cannot open Printer Device!" : Endif

instruction: open the standard printer device for use
Printer Open

This command opens the printer device using your current preferences.

instruction: close printer port
Printer Close

Use this instruction to close the printer port that has been previously set with a PRINTER OPEN command. Note that the memory is not freed for use by your AMOS Professional program immediately. Memory is only returned if the following conditions are met: firstly, that no other program has requested the printer device during multi-tasking, as explained above. Secondly, if the system becomes short of memory and requires more.

instruction: send a string to the printer
Printer Send text$

The PRINTER SEND command sends a string of text to the printer, using multi-tasking.

Back    Next