rm-hull / luma.lcd

Python module to drive PCD8544, HT1621, ST7735, ST7567 and UC1701X-based LCDs
https://luma-lcd.readthedocs.io
MIT License
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Comment error: HT1621 may actually 1/3 bias #165

Open xobs opened 1 year ago

xobs commented 1 year ago

The following code appears to indicate that the HT1621 driver is using 1/2 Bias:

https://github.com/rm-hull/luma.lcd/blob/990716efc662210a265d8dbc14a8958da5723b8e/luma/lcd/device.py#L922

However, my understanding of the command format of luma.lcd is that this is actually setting 1/3 Bias:

image

The comment should be updated, or the code should be changed to 0x50 in order to use 1/2 Bias

thijstriemstra commented 1 year ago

The comment should be updated, or the code should be changed to 0x50 in order to use 1/2 Bias

@xobs did you try if it still works properly (or even better) when changing the code to use 0x50?

xobs commented 1 year ago

For me, I had to use 1/3 bias in order to get the display to show anything. But the bias level depends on the display, so it varies from panel to panel.