MCP3201 5V version accuracy seems to be 0.2%

So I did the test.  I thought it might take me 30 minutes to debug the hardware wrong connections.  But again, everything went smoothly.

Accuracy seems not too different from the 3V3 version.  But then I forgot to check the precise value of the reference voltage.  So I need to Excel again.
Using the rough value 5.00, accuracy is 6 digits out of 12.  If using the more accurate value of 4.96, accuracy becomes 3 digits.  So accuracy is 3 last digits.

I am not too sure if I can then say accuracy is 3 digits / 12 digits == 8 / 4096
= 0.19 = 0.2%.

If indeed it is 0.2%, then it is very good.

5V0  
MCP3201 = 0001111111110010
Excel   =    111111111111

0V0  
MCP3201 = 0000000000000010
Excel   =    000000000000

3V26
MCP3201 = 0001010011111101
Excel   =    101001101111

2V43
MCP3201 = 0000111110100111 test 1
          0000111110101010 test 2
Excel   =    011111000111 (using 5.00)
             011111010111 (using 4.96)


*** Results ***

*** Start testing MCP3201 ADC ***

5V0 

ADC output byte 1 =  00011111
ADC output byte 2 =  11110010

*** Stop testing MCP3201 ***


*** Stop Program ***

pi@raspberrypi ~/python_programs/test_guzuntypi $ sudo python fl2067.py

*** Start Program - MCP3201 ADC 01   ***


*** Start testing MCP3201 ADC ***

0V 

ADC output byte 1 =  00000000
ADC output byte 2 =  00000010

*** Stop testing MCP3201 ***


*** Stop Program ***

pi@raspberrypi ~/python_programs/test_guzuntypi $ sudo python fl2067.py

*** Start Program - MCP3201 ADC 01   ***


*** Start testing MCP3201 ADC *** 

3.26V

ADC output byte 1 =  00010100
ADC output byte 2 =  11111101

*** Stop testing MCP3201 ***


*** Stop Program ***

*** Start testing MCP3201 ADC ***

2.43V

ADC output byte 1 =  00001111
ADC output byte 2 =  10100111

*** Stop testing MCP3201 ***


*** Stop Program ***



*** Start testing MCP3201 ADC ***

ADC output byte 1 =  00001111
ADC output byte 2 =  10101010

*** Stop testing MCP3201 ***


*** Stop Program ***

.END