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Hi, i just bought KS868-A16 Rev1.6 and i have problems connecting a serial LCD.
Port connected P19
LCD-serial controller PC8574T
LCD model 20x4
Testet whith 3,3V also whith 5V
Scan whith Arduino i2c scanner no results.
LCD tested on Arduino Uno is ok.
KC868-A16 tested whith a simplet test IO ok.
Try whith simple Arduino examples i2c LCD
Try wired the LCD examples SCL/SDA to IO 4/5
Any help please?
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you need to check your serial LCD RXD and TXD voltage level, 3.3v or 5v?
you using serial LCD, how to check with i2c scan???
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“you using serial LCD, how to check with i2c scan???”
i don’t understand ,serial LCD use i2c, and yes i2c scan need to see LCD i2c controller.
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i don't understand you. why serial LCD will use i2c??? take a photo, how you wire and your LCD.
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I use PCF8574 I/O-I2C for LCD(i use whith Arduino whith no problem)
Attached are a pic whith adapter/driver for LCD.
Attached Files
Image(s)
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don't use serial LCD for PCF7574 GPIO, you should connect them with ESP32's pin directly.
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Ok, so need to solder I2C LCD to 21/22 Pin of ESP32?
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A16 board already have I2C extender on PCB.
i really don't understand your question. you said your LCD is serial, now you said it's I2C LCD?