error : object with buffer protocol required

[bellad]

hello,
with my little prog i have error : object with buffer protocol required

can you help , thank

Code: Select all

from machine import Pin, ADC
import time
amp = ADC(Pin(34))# amperage du moteur
amp.atten(ADC.ATTN_11DB)
BTN = Pin(13, Pin.IN, Pin.PULL_UP)
a=0
b=0
while True:
  time.sleep(0.25)
  a = amp.read() * 0.000805
  if a > b :
    b=a
    print(b)#amperage le plus fort
  if BTN.value() == 0 :
    f = open('a.txt', 'w')  # Fichier ampere
    f.write(b)  # line 19
    f.close()
    break

with webrepl :

Code: Select all

>>> import amp                                                                                                                                        
1.46671                                                                                                                                               
1.480395                                                                                                                                              
1.491665                                                                                                                                              
1.50374                                                                                                                                               
1.520645                                                                                                                                              
1.53111                                                                                                                                               
Traceback (most recent call last):                                                                                                                    
  File "<stdin>", line 1, in <module>                                                                                                                 
  File "amp.py", line 19, in <module>                                                                                                                 
TypeError: object with buffer protocol required  

[Roberthh]

f.write() requires a string or byte array or bytes object as argument, not a number. You have to convert b to a suitable data type, like with str( b).

[bellad]

oups !! , thank you
sorry