Degrees to decimal conversion

[RFsolution]

Hi Darrel,

Thanks a lot this is working perfect

Imagine if I would like to do the opposite

so from a 10 or 12bit value (representing 1 revolution) to deg.xx
Can you put me on the right tracks to do that ?

Decimal_value_10bit var word '(0-1024)
Decimal_value_12bit var word '(0-4098)
degrees var word '(0-360)
degrees_fraction var byte '(.xx)
degree_Total var word

[Darrel Taylor]

Imagine if I would like to do the opposite

so from a 10 or 12bit value (representing 1 revolution) to deg.xx
Can you put me on the right tracks to do that ?

It's essentially the same thing, with the order of the formula reversed.

Originally for degrees to 16-bit we had ...
65536 * degrees / 36000 (notice I've changed the constants)

The reverse would be ...
16-bit * 36000 / 65536

You can change between any of the scales by simply changing the order and the constants.

degrees to 12-bit ... degrees * 4096 / 36000
12-bit to degrees ... 12-bit * 36000 / 4096

degrees to 10-bit ... degrees * 1024/ 36000
10-bit to degrees ... 10-bit * 36000 / 1024

Here's a macro for N-Bit_Math that will let you do it easily ...

ASM
Convert  macro WFrom, Frange, WTo, Trange
    MOVE?WP   WFrom,  _Temp1              ; copy From value to Temp1 Pvar
    MOVE?CP   Frange, _Range1             ; put From Range in Range1 Pvar 
    MOVE?CP   Trange, _Range2             ; put To range in Range2
    MATH_MUL  _Temp1, _Range2, _Temp1     ; Temp1 = From * To_Range
    MATH_DIV  _Temp1, _Range1, _Temp1     ; Temp1 = Temp1 / From_Range
    MOVE?PW   _Temp1, WTo                 ; copy result to word variable WTo 
  endm
ENDASM

Then you can convert any of the scales to any other scale by providing the macro the From value with the "range" that variable goes to, a variable to put the result in and the range that variable should span.

To convert the original degrees to 16-bit, you would ...

@   Convert _degree_Total, 36000, _Decimal_value_16bit, 65536

or to 12-bit ...

@   Convert _degree_Total, 36000, _Decimal_value_12bit, 4096

Going the other way is just as easy.

@   Convert _Decimal_value_16bit, 65536, _degree_Total, 36000
@   Convert _Decimal_value_12bit,  4096, _degree_Total, 36000

Here's a test program ...

<font color="#000000">rxd                 <b>VAR </b>PORTC.7
txd                 <b>VAR </b>PORTC.6
<b>HIGH </b>txd

Decimal_value_16bit <b>VAR WORD </b><font color="#000080"><i>'(0-65535)
</i></font>Decimal_value_12bit <b>VAR WORD </b><font color="#000080"><i>'(0-4095)
</i></font>degrees             <b>VAR WORD </b><font color="#000080"><i>'(0-359)
</i></font>degrees_fraction    <b>VAR BYTE </b><font color="#000080"><i>'(.xx)
</i></font>degree_Total        <b>VAR WORD

</b><font color="#000080"><i>'----[N-Bit Math]---------------------------------------------------------------
</i></font>PRECISION  <b>CON </b>4 SYSTEM          <font color="#000080"><i>; 4 bytes=32-bit
</i></font><b>INCLUDE </b><font color="#FF0000">&quot;N-Bit_MATH.pbp&quot;

</font>Temp1    <b>VAR BYTE</b>[PRECISION]
Range1   <b>VAR BYTE</b>[PRECISION]
Range2   <b>VAR BYTE</b>[PRECISION]

<b>ASM
</b><font color="#008000">Convert  macro WFrom, Frange, WTo, Trange
    MOVE?WP   WFrom,  _Temp1              </font><font color="#000080"><i>; copy From value to Temp1 Pvar
    </i></font><font color="#008000">MOVE?CP   Frange, _Range1             </font><font color="#000080"><i>; put From Range in Range1 Pvar 
    </i></font><font color="#008000">MOVE?CP   Trange, _Range2             </font><font color="#000080"><i>; put To range in Range2
    </i></font><font color="#008000">MATH_MUL  _Temp1, _Range2, _Temp1     </font><font color="#000080"><i>; Temp1 = From * To_Range
    </i></font><font color="#008000">MATH_DIV  _Temp1, _Range1, _Temp1     </font><font color="#000080"><i>; Temp1 = Temp1 / From_Range
    </i></font><font color="#008000">MOVE?PW   _Temp1, WTo                 </font><font color="#000080"><i>; copy result to word variable WTo 
  </i></font><font color="#008000">endm
</font><b>ENDASM

</b><font color="#000080"><i>'----[Main Program Loop]--------------------------------------------------------
</i></font>Main:
    <b>SEROUT2 </b>txd,84,[13,10,<font color="#FF0000">&quot;Enter Degrees (Max=359.99): &quot;</font>]
    <b>SERIN2 </b>rxd,84,[<b>DEC </b>degrees,<b>DEC2 </b>degrees_fraction]
    Degree_Total = degrees * 100 + degrees_fraction

    <font color="#000080"><i>;--- degrees to 16-bit ---
</i></font><font color="#008000">@   Convert _degree_Total, 36000, _Decimal_value_16bit, 65536
    </font><b>SEROUT2 </b>txd,84,[13,10,<font color="#FF0000">&quot;16-bit: &quot;</font>,<b>HEX4 </b>Decimal_value_16bit,<font color="#FF0000">&quot;  &quot;</font>,<b>DEC </b>Decimal_value_16bit,13,10]

    <font color="#000080"><i>;--- degrees to 12-bit ---
</i></font><font color="#008000">@   Convert _degree_Total, 36000, _Decimal_value_12bit, 4096
    </font><b>SEROUT2 </b>txd,84,[<font color="#FF0000">&quot;12-bit: &quot;</font>,<b>HEX4 </b>Decimal_value_12bit,<font color="#FF0000">&quot;  &quot;</font>,<b>DEC </b>Decimal_value_12bit,13,10]

    <font color="#000080"><i>;--- 16-bit to degrees ---
</i></font><font color="#008000">@   Convert _Decimal_value_16bit, 65536, _degree_Total, 36000
    </font><b>SEROUT2 </b>txd,84,[<font color="#FF0000">&quot;Deg from 16-bit: &quot;</font>,<b>DEC </b>degree_Total/100,<font color="#FF0000">&quot;.&quot;</font>,<b>DEC2 </b>degree_Total,13,10]

    <font color="#000080"><i>;--- 12-bit to degrees ---
</i></font><font color="#008000">@   Convert _Decimal_value_12bit, 4096, _degree_Total, 36000
    </font><b>SEROUT2 </b>txd,84,[<font color="#FF0000">&quot;Deg from 12-bit: &quot;</font>,<b>DEC </b>degree_Total/100,<font color="#FF0000">&quot;.&quot;</font>,<b>DEC2 </b>degree_Total,13,10]

<b>GOTO </b>Main

And here's some output from the test program ...