README.md
mexdulon Arduino Nano Shield Numbers

This project is for the Arduino Nano Shield, uses I2C at Port B and Z for display 
multiplexing. The display output is X and Y as usual.




  
Port
  
Function




  
A
  
Mode Output (binary)


  
B
  
I2C (A4,A5)


  
X
  
Display Out 1


  
Y
  
Display Out 2


  
Z
  
Display Multiplexing







  
Value
  
Format
  
Output




  
0
  
NUL
  
- Empty -


  
1
  
OCT
  
Octal


  
2
  
HEX
  
Hexadecimal


  
3
  
DCU
  
Decimal Unsigned


  
4
  
DCS
  
Decimal Signed


  
5
  
FXU
  
Fixed-Point Number Unsigned


  
6
  
FXS
  
Fixed-Point Number Signed


  
7
  
FLU
  
Floating-Point Number Unsigned


  
8
  
FLS
  
Floating-Point Number Signed




OCT: Octal

The value is displayed in three octal digits (0..7).

HEX: Hexadecimal

The value is displayed in two hexadecimal digits:




  
Value
  
Output




  
0..9
  
0..9


  
10
  
A


  
11
  
b


  
12
  
C


  
13
  
d


  
14
  
E


  
15
  
F




DCU: Decimal Unsigned

The value is displayed as unsigned integer in decimal (0..255).

DCS: Decimal Signed

The value is displayed as signed integer in decimal (-128..127). The format is two's complement.

FXU: Fixed-Point Number Unsigned

The value is displayed as decimal (positive) number with the decimal point (e.g. 15.9375).
The format is 4 bits for the value behind the decimal point and 4 bits before it.
So the values of the bits is as follows: |8|4|2|1|0.5|0.25|0.125|0.0625|

FXS: Fixed-Point Number Signed

The value is displayed as decimal (signed) number with the decimal point (e.g. -8.9375).
For negative numbers, the two's complement is used. See also FXU.

FLU: Floating-Point Number Unsigned

The value is interpreted as floating point (unsigned) number. The display shows the significant and the exponent seperated by a superscript -. The significant is 4 bits and the exponent is 4 bits.

FLS: Floating-Point Number Signed

The value is interpreted as floating point (signed) number. The display shows the significant and the exponent seperated by a superscript -. The MSB of the significant is the sign bit (1 for minus). The exponent uses the two's complement format. The significant is 4 bits and the exponent is 4 bits.