| Thread Review (Newest First) |
| Posted by RaspberryP9999 - Yesterday, 02:57 |
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Hi Hans, Yes, it outputs 16x2 to the 20x4 screen while using: USE_I2C_LCD = True The output shows on the Top 2 lines, while the bottom 2 lines are blank (as well as the last 4 characters), eg: xxxxxxxxxxxxxxxx____ xxxxxxxxxxxxxxxx____ ____________________ ____________________ Changing to "USE_I2C_LCD = 20x4" as the Guest recommended results in a blank screen. Upon re-reading the Guest's post, I think by "Confirm it works", they may have intended to say "Make sure your screen is functional", rather than "Yes I am confirming that 20x4 works" ? If you have an alternate build, I can test it on my screen. |
| Posted by hansehv - 29-06-25, 19:58 |
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Hi, This gets interesting as this could be the first confirmation of 4 working lines. So @guest: can you please confirm its indeed 4 lines and whether you had to do something extra. Many thanks ! I've introduced this coding in may 2020 with a note in the changes.txt: Code: - Added I2C-LCD (HD44780, 2x16 and 4x20).Several users have struggled to get it working with 2 lines, in most cases solved with checking wires or the backlight screw (please search the forum for the applicable threads if you want to see all details). There's only one feedback regarding 4 lines: s1100 (unregistered user) reporting "not working for4 lines, only 2", with a typical detail: Quote:Config info: At that time I was absent, but looking at it now, the "16x2 no output" intrigues me as this suggests a coding error, however I cannot reproduce this. Lacking this hardware I can only perform "dry" tests. @RaspberryP99: Do you have the same? If so: would you be so kind to register as forum user, so that I can can send you some test/debug material via private messages that would help in finding a fix. Regards, Hans |
| Posted by RaspberryP99 - 29-06-25, 02:38 |
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[quote pid="589" dateline="1751125754"] Confirm it works, that is: with I2C-HD44780. You have to configure "USE_I2C_LCD = 20x4" in the configuration.txt. See docs. [/quote] Yes, I have "USE_I2C_LCD = 20x4" in the configuration. The output is still utilizing only 2 lines and 16 characters (16x2). The other lines/characters are unused/blank. Can you clarify, by "Confirm it works", do you mean A. "I see it in the docs, so it should work", or B. "I'm personally using a 20x4 screen" ? |
| Posted by - 28-06-25, 15:49 |
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Confirm it works, that is: with I2C-HD44780. You have to configure "USE_I2C_LCD = 20x4" in the configuration.txt. See docs. |
| Posted by RaspberryP99 - 28-06-25, 02:31 |
| Instructions/documentation says SamplerBox works with 20 X 4 LCD screens -- Is this an error/incorrect? |