I2C tests with the Sparkfun SerLCD qwiic LCD

I2C_tests.py

"""
This is a test for an error on the Sparkfun SerLCD
> OSError: [Errno 19] Unsupported operation

Tested on:
- QT PY RP2040 using the STEMMA QT port
- SparkFun 16x2 SerLCD - RGB Backlight (Qwiic)

The errors seems to happen when many writes are done in fast succession.
DELAY = 0 -> Almost always errors at a seemingly random number of characters.
DELAY = 0.001 -> Seems to completely remove the error.
"""
import board
import busio
import random
import time

DELAY = 0.001 # 0
STRING_LEN = 1
TEST_STRING = chr(random.randint(ord("A"),ord("z"))) * STRING_LEN
NUM_WRITES = 32

i2c = busio.I2C(sda=board.SDA1, scl=board.SCL1)
try:
    while not i2c.try_lock(): i2c.unlock()
    i2c.writeto(0x72,"|-") # clear
    for x in range(NUM_WRITES):
        time.sleep(DELAY)
        i2c.writeto(0x72,TEST_STRING)
    i2c.unlock()
    print("GOOD")
except Exception as ex:
    import sys
    sys.print_exception(ex)
    print("BAD",x)
finally:
    i2c.deinit()

print("FIN")