Programming instructions

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Intermec Fingerprint 6.13 – Programmer's Guide
12. Breaking Execution
5. FINGERPRINT PROGRAMMING, cont'd.
Continued!
In chapter 2 “Getting Started” at the beginning of this manual, the
methods of breaking a startup program was briefly explained.
Startup programs (autoexec files) start up automatically when the
printer is turned on and continues to run infinitely by means of some
kind of loop.
In printer models provided with a keyboard, you can – by default –
break a program by pressing the <C> key and keep it pressed while
you also press down the <Pause> key. There is no such default
facility in printers without keyboard! Unless the startup program
contains facilities for breaking the execution or the printer is
provided with a keyboard, it will be impossible to make the printer
do something else but keep on running the same program. It will
also be difficult to check the printer if some kind of error occurs.
The only remaining way to stop a startup program, which contains
no break facilities, is to physically remove the part of the memory
where the program resides, i.e. the configuration EPROM pack-
ages, the RAM packages or a memory card. Therefore, it is strongly
recommended always to include break facilities in startup pro-
grams, especially when the program is to be used in a printer without
keyboard.
Four instructions can be used for providing a program with a break
interrupt facility:
BREAK Specifies an interrupt character.
BREAK...ON Enables break interrupt.
BREAK...OFF Disables break interrupt.
ON BREAK...GOSUB... Branches the execution to a sub-
routine when a break interrupt is
executed.
In all break-related instructions, the serial communication channels
and the keyboard are referred to by numbers:
0 = "console:" (i.e. the printer's keyboard)
1 = "uart1:"
2 = "uart2:"/"rs485:"
3 = "uart3:"
BREAK does not work on the parallel Centronics channel.