LEX    'ENGLEX'
        ID     #5E
        MSG    0
        POLL   0
FNRTN4  EQU    #0F238   exit for functions
STR$SB  EQU    #18149   internal number to string conversion, uses current fmt
DSPFMT  EQU    #2F6DC   storage for N the display mode flags. Also, at
*              #2F6DD   we have the # of display digits data.
        ENTRY  ENG$
        CHAR   #F
        ENTRY  FIX$
        CHAR   #F
        ENTRY  SCI$
        CHAR   #F
        KEY    'ENG$'
        TOKEN  #B0      THIS TOKEN ALLOCATION IS SUBJECT TO CHANGE!
        KEY    'FIX$'
        TOKEN  #B1
        KEY    'SCI$'
        TOKEN  #B2
        NIBHEX 1FF
*****************************************************
*
* Syntax: A$=ENG$(X [,Y])      where X is the number to be converted to
*      a string in ENG Y format, without disturbing the current format
*      setting.
*      A$=ENG$(X) uses the value last set with FIX Y, SCI Y or ENG Y
*      to specify the # of digits to be shown.
*
* This keyword can help speed-up numeric tabulations by avoiding the
* use of DISP USING or PRINT USING. Instead, use TAB, or O$[N]=ENG$(X,Y)..
*
* The ENG$ keyword suggested itself after I wrote the INT$ keyword.
* I usually prefer using the STD display format, but I also often
* want to print or display data in ENG 5 format. So, rather than
* toggle back and forth between modes, a new keyword!
*
* Why not DISP USING? ... Because USING is slow!
*
* It should be noted that if you do ENG 5 @ STD, the
* default number of integers / flags remain unchanged at 5.
* This means that you can either preset this value as shown above,
* or override this information with the optional parameter..
*
*     Coded by M. Markov  in April '87
*
* While we are here, we might as well provide the equivalent functions
* for PRINTing or DISPlaying numbers in the FIX ? or SCI ? mode formats.
* This can be done with almost no additional code, since the only change
* required is one nib in the LCHEX instruction. We could also provide STD
* formating, but that keyword is already provided by the DATALEX...
*
********************************************************************
        NIBHEX 8812      one mandatory numeric character, one opt. numeric
ENG$    GOSUB  ENGSUB
        LCHEX  3
        GONC   ENGDO    
        NIBHEX 8812
FIX$    GOSUB ENGSUB
        LCHEX  1
        GONC   ENGDO
        NIBHEX 8812
SCI$    GOSUB ENGSUB
        LCHEX  2
        GONC   ENGDO
ENGSUB  P=C    15        number of parameters used
        CD0EX           get PC into C[A]
        CSLC            shift PC left one nib
        CSLC            again. C[B] is now available
        D0=(5) DSPFMT   pointer to display format data
        C=DAT0 B        save display format in C[B]
        R3=C            save PC and current display FMT in R3
        ?P=    1        only one parameter?
        GOYES  ENGdef   yes, use existing # of digits (default)
        GOSBVL MPOP1N   no, get the desired # of digits
        GOC    argerr   
        GOSBVL FLTDH    convert value to hex
        D0=D0+ 1        store in 2F6DD ==> (DSPFMT)+1, one nibble
        DAT0=A 1
        D0=D0- 1        reset pointer for later use
        D1=D1+ 16       move pointer to mandatory argument
ENGdef  P=     0        the start of common code...
        C=0    W        clear C[W]
        RTNCC           set DSPFMT to ENG. (STD= 0, SCI= 2 & ENG= 3)
ENGDO   DAT0=C 1
        GOSBVL STR$SB   does POP1N, convert to string using FIX 0 mode
        C=R3            get back PC and original display format
        DAT0=C B        restore display format (D0 is unchanged)
        CSRC            Shift PC back into C[A] field
        CSRC
        CD0EX           restore PC
        GOVLNG #0F23C   EXPR reset stack pointer and exit.
argerr  GOVLNG ARGERR
ARGERR  EQU    #0BF19
MPOP1N  EQU    #0BD8D
FLTDH   EQU    #1B223