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- Docs for Swprt.com - printer switching utility
- R. Trevithick, 12/24/87
-
-
- This allows people with multiple parallel ports to send normal
- LPT1 output to any of them. What it actually does is switch the
- port assignments in low memory. It's handy when using dumb
- programs which can't deal with multiple printers. Each time it's
- run, it prints a message on the screen to indicate which printer
- port is currently assigned to LPT1.
-
- Syntax: swprt [/1..3] [/q]
-
- To actually change port assignments, use the following command line
- parameters:
-
- /1 assigns normally to 1st parallel port (LPT1 default)
- /2 assigns to 2nd parallel port
- /3 assigns to 3rd parallel port
-
- To run quietly (no messages printed, for batch files etc.):
-
- /q
-
- If used with no option, it merely reports which port (i.e., printer)
- is assigned without changing anything.
-
- Make sure your machine is set back to normal (printer #1) before
- using programs that DO know about multiple printers (e.g.
- WordPerfect). Note that printer #1 is the one which is assigned
- when the machine is first booted.
-
- A word of warning: if you try to send output to a parallel port
- which doesn't exist, you'll probably end up having to reboot. At
- least that's what happens on my machines...
-
- Perhaps a bit more explanation is in order here. Let's say you
- have three parallel printer ports on your machine. Number one is hooked
- to a dot matrix printer, number two to a letter quality impact printer,
- and number three to a laser printer. Typing 'COPY PR.DOC > PRN' would
- initially print this file on the dot matrix printer. After running
- swprt /2, the same command would print to the letter quality printer,
- and after running swprt /3 the output would be to the laser printer.
-
-
- Technical Notes:
-
- Swprt switches ports by first examining the low memory addresses for each
- of the three parallel printers. When a request is made to change
- assignments (via /1 /2 or /3), the program first normalizes the values
- to the defaults. If the request is a /1, we are done at this point. If
- it's a /2 or /3, the program switches the LPT1 assignment with the
- assignment of the requested port (LPT2 or LPT3). Hence, after switching
- to parallel port 3, for example, LPT1 output will go to parallel port 3,
- LPT3 output will go to parallel port 1, and LPT2 output will remain
- unchanged and continue to go to parallel port 2.
-
-
- -------------Changes as of 12/15/87 revision----------------
-
- - Ported over for Turbo C compiler (original was Datalight.) Code size
- reduced from 8K to 4K.
- - Eliminated all 'illegal' code, such as direct video writes. Should run
- on any MS-DOS machine now.
-
- -------------Changes as of 12/24/87 revision----------------
-
- - Minor changes; reduced size a bit
-
-
- Bob Trevithick GEnie address: R.TREVITHICK
- Information Services Department
- Newark DDSO
- 703 E. Maple Ave
- Newark, NY 14513
-
- Days: (315) 331-1700 Ext. 2658
- Eves: (315) 331-5266
-