I have a question about using PiicoDev components with the prototyping cable when the expansion board is NOT used.
The Cable SKU: CE07796 PiicoDev Prototyping Cable (Male) 200mm for example has these notes on the cable colors
- Black for GND
- Red for V+ with PiicoDev and Qwiic boards that are 3.3V
- Blue for SDA GPIO16(Pin21)
- Yellow for SCL GPIO17(Pin22).
However, when I connect the RFID module in this way and run this code on the pico:
from PiicoDev_RFID import PiicoDev_RFID
from PiicoDev_Unified import sleep_ms
from PiicoDev_SSD1306 import *
rfid = PiicoDev_RFID() # Initialise the RFID module
print(‘Place tag near the PiicoDev RFID Module’)
print(rfid)
while True:
if rfid.tagPresent(): # if an RFID tag is present
id = rfid.readID() # get the id
if (id == “CB:61:B8:08”):
print(“9”)
else:
print(id)
sleep_ms(100)
I see this error:
Traceback (most recent call last):
File “”, line 6, in
File “/lib/PiicoDev_RFID.py”, line 79, in init
File “/lib/PiicoDev_RFID.py”, line 284, in reset
File “/lib/PiicoDev_RFID.py”, line 95, in _wreg
OSError: [Errno 5] EIO
When using the PiicoDev Cable 100mm SKU: CE07773 which has a 4-wire harness with 1mm pitch SH connectors on each end, the code works as expected.
So my question is, how can I use the prototyping cable with the male headers for situations when I am not using an expansion board? Why is SDA associated with GPIO16(Pin21) and the SCL pin is associated with the GPIO17(Pin22)? What do SDA and SCL mean? Do I need to configure the SDA/SCL pins manually?
I note there are similar questions to this but I didn’t not find a solution yet.
