Review on 📺 SunFounder IIC I2C TWI 1602 Serial LCD Module Display for Arduino R3 Mega 2560 16x2 - Enhanced Arduino Display for Projects by Dexter Rasberry

The LCD panel works fine, but the LCD controller from an unnamed semi-finished product is complete junk. The specification document PK-10290_410 is incomplete and does not fully conform to the industry standard HD44780. For example, an LCD is an extremely slow device that requires the programmer to check the Busy Flag (BF) bit before sending any command/data. On this hardware, the LCD is busy all the time, and without checking/clearing that bit, it sends garbage characters. Built-in CGROM - complete bullshit. When I send the number value "1" to the display, the LCD shows "q". It has a problem with interpreting the high 4 bits in CGROM, so all characters using "0010xxxx" in the upper 4 bit ranges become "0111xxxx". This is not an isolated problem; I sent back the first block and tested the second. I'm not at all surprised by Revain's rating. I should have spent a little more and gotten a function block from DigKey.