PRINTER ONLINE
function: report if printer is on-line
status=Printer Online
This useful function provides a simple method of checking if the printer is connected and ready for use. It returns a value of -1 (True) if the printer is on-line, otherwise zero (False) will be given. This function only works with parallel printer devices.
PRINTER ERROR
function: check for an error in printing operation
status=Printer Error
Use this function to check if the current printing operation is proceeding normally. A value of zero suggests that all is well, but any other value indicates an error.
PRINTER BASE
function: get the address of printer base
address=Printer Base
The PRINTER BASE function is used to return the address of the i/o structure used to control the printer. It is intended for use by skilled operators only! Poking around the internal device structures is a very dangerous operation indeed!
Other ports and devices
The serial Port is examined in the next Chapter, and it is also possible to access the parallel port
directly, which provides a number of advantages over the printer device. Please refer to Chapter
10.5 for full details.
The complete control and exploitation of other devices that control hardware as well as internal features of the Amiga is dealt with in Chapter 11.5. This Chapter ends with a general instruction and function for dealing with ports.
OPEN PORT
instruction: open a channel to an 10 port
Open Port channel number,"PAR:"
Open Port channel number,"SER:"
Open Port channel number,"PRT:"
The three versions of the OPEN PORT command are shown above, and they are used to open a channel to the Parallel Interface, or the RS232 Port, or the printer chosen in your preferences settings. All standard sequential file commands can be performed as usual, except for commands that are specific to disc operations, such as LOF and POF.