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dhylands / python_lcd

Python based library for talking to character based LCDs.
MIT License
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rp2 PIO variant #31

Closed robert-hh closed 2 years ago

robert-hh commented 3 years ago

Hi Dave. This is a non-issue. I have adapted the GPIO version of the driver for the RP2040 using PIO. Just as an exercise. I added the ZIP package. If one takes care to wire the RW pin to GND before applying power, there is no risk of damage, since then all LCD pins are used as input. I have tested it with an LCD in four bit mode only, and the 8 bit mode just with a logic analyzer.

robert-hh commented 3 years ago

There might have been a bug in that. I might have a problem with loose wires. Nevertheless, here is another version which makes the double nibble send magically in the state machine.

rp2_pio_lcd.zip

Edit: After using properly soldered wires things are more stable. Even at 500kHz.