INT 28 u - PCXDUMP v9.00+ - INSTALLATION CHECK                                  
	AX = 9999h
Return: AX = AAAAh if installed
	    CX = version number * 100 (example: 03A2h = 930 = v9.30)
	    DL = interrupt used by the dump function (see #02553)
		(00h if call not available)
	    BX = CS of PCXDUMP's INT 28 handler (undocumentedInformation about a product which is not publicly available from the manufacturer, and must be determined by reverse-engineering (disassembly, trial-and-error, etc.).	 Undocumented information tends to change -- often dramatically -- between successive revisions of a product, since the manufacturer has no obligation to maintain compatibility in behavior which is not explicitly stated.)
	    ES = segment of PCXDUMP's memory block (v9.30, undocumentedInformation about a product which is not publicly available from the manufacturer, and must be determined by reverse-engineering (disassembly, trial-and-error, etc.).	 Undocumented information tends to change -- often dramatically -- between successive revisions of a product, since the manufacturer has no obligation to maintain compatibility in behavior which is not explicitly stated.)
Program: PCXDUMP is a shareware screen grabber saving in PCX format
Notes:	if DL<>00h a dump can be requested by calling INT DL as shown
	  below (the user can choose the interrupt number at installation
	  time); if DL=00h the dump function can be called only by hotkeys
	  (this is the default)


(Table 02553)
Call PCXDUMP screen-dump function with:
	INT xx
	AX = 1234h
	BX = dump type
	    0000h Color dump
	    0001h Immediate color dump
	    0002h Black/White dump
	    0003h Immediate B/W dump
	    0004h Inverted B/W dump
	    0005h Gray scaled dump
	    0006h Inverted gray scaled dump
	    0007h Text screen dump to text file
	    0008h Text screen dump to ansi file
Return: nothing
Notes:	if BX=0001h, 0003h, 0007h or 0008h the whole screen will be
	  dumped; the other valid values will draw a selection frame
	  on the screen except in text modes (text modes allow only
	  full screen dumps)
	this function doesn't perform the dump, it only requests it;
	  the dump will be performed after a few milliseconds if it's
	  safe to do so, thus the author recommends putting a 60 ms delay
	  after this call