In SX Microcontrollers, SX/B Compiler and SX-Key Tool, mrchadwickusa wrote:

Hi John,

 

Here is a revised version that uses WDATA to look up the divisor.  I also changed the test order to speed that up a little.  Converting 12345d the original with the wrdDivisor= wrdDivisor / 10 took 505.5 us at a 4Mhz clock, using the data statements it takes 130.5 uS.  This compares to 45.25 for the assembly version using Golovchenko's code.  I'm going to do an SXB version of Golovchenko's code using the data lookup to see how that compares.  In the mean time, here is the revised subtract by powers of 10 code using WDATA with work around for the READ bug when using word values.

 

I also made a tiny change that allows you to set BLANK as a constant to either 0, if you want BCD nibbles, or $30 if you want ASCII digits.



[code]
'---------------------------------------------------------------------------
Bin16DEC:
' Use: Bin16DEC word
' -- Convert a 16bit binary variable into a decimal value. 

'    define BLANK as 00h for BCD nibbles
'    define BLANK as 30h to directly output ASCII
'    to a terminal or LCD.
'    Original versions by Bean (Hitt Consulting) & Michael Chadwick
'
' Setup
'    wrdTemp    var WORD
'    wrcDivisor var WORD
'    ascDigit   var Byte(5)
 
   IF __PARAMCNT = 1 THEN   ' if parameter is a Byte or Word variable
     wrdTemp = __PARAM1
   ELSE
     wrdTemp = __WPARAM12
   ENDIF
 
   ' fill all locations with blanks
   PUT ascDigit(0), BLANK, BLANK, BLANK, BLANK, BLANK  'updated line
 
   x1 = 4                                    ' position in array
   wrdDivisor = -10000                        ' set initial power of 10 

  

Bin16DEC1:
   inc ascDigit(x1)        ' assume we will succeed in subtraction
   wrdTemp = wrdTemp + wrdDivisor      ' try the subtraction
   if C = 1 then Bin16DEC1       ' OK, try again
   dec ascDigit(x1)
   wrdTemp = wrdTemp - wrdDivisor
   dec x1                                    ' decrement position counter
   if x1 = 0 THEN Bin16DEC2                  ' more digits to process?
   x1= x1 SHL 1         ' * 2 as a work around for the read bug
   READ divisors + x1,  wrdDivisor
   wrdDivisor= 0-wrdDivisor
   x1= x1 SHR 1         ' / 2 as work around for the read bug
   goto Bin16DEC1 

  

Bin16DEC2:
   ascDigit(x1) = ascDigit (x1) + wrdTemp_LSB   ' take care of last (right most) digit
  RETURN   

  

divisors:
 WDATA 1,10,100,1000
 
[/code]

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