DDoFmt() 
     DGetChar() 
     DGetNum() 
     DMayGetChar() 
     DPutChar() 
     DPutFmt() 
     DPutStr() 
     KCmpStr() 

   NAME
	DDoFmt -- format data into a character stream.

   SYNOPSIS
	DDoFmt(FormatString, DataStream, PutChProc, PutChData);
	      A0	    A1		A2	   A3

   FUNCTION
	perform "C"-language-like formatting of a data stream,
	outputting the result a character at a time

   INPUTS
	FormatString - a "C"-language-like null terminated format
		string, with the following supported % types:
	DataStream - a stream of data that is interpreted according to
		the format string.
	PutChProc - the procedure to call with each character to be
		output, called as:
	    PutChProc(Char,  PutChData);
		      D0-0:8 A3
		the procedure is called with a null Char at the end of
		the format string.
	PutChData - an address register that passes thru to PutChProc.

   NAME
	DGetChar - get a character from the parallel port

   SYNOPSIS
	char = DGetChar()
	D0

   FUNCTION
	get the next character from the parallel port.

   NAME
	DGetNum - get a number from the parallel port

   SYNOPSIS
	number = DGetNum()
	D0

   FUNCTION
	get a signed decimal integer from the parallel port.

   NAME
	DMayGetChar - return a char iff present, but don't block

   SYNOPSIS
	flagChar = DMayGetChar()
	D0

   FUNCTION
	return either a -1, saying that there is no char present, or
	the char that was waiting

   NAME
	DPutChar - put a character to the parallel port

   SYNOPSIS
	char = DPutChar(char)
	D0	       D0

   FUNCTION
	put a character to the parallel port.

   NAME
	DPutFmt - print formatted data to the parallel port

   SYNOPSIS
	DPutFmt(format,values)
	       A0     A1

   FUNCTION
	print formatted data to the parallel port

   NAME
	DPutStr - put a string to the parallel port

   SYNOPSIS
	DPutStr(string)
	       A0

   FUNCTION
	put a null terminated string to the parallel port.

   NAME
	KCmpStr - compare two null terminated strings

   SYNOPSIS
	mismatch = KCmpStr(string1, string2)
	D0		  A0	   A1

   FUNCTION
	string1 is compared to string2 using the ASCII collating
	sequence.