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Sam_40
Joined: 07 Jan 2015 Posts: 127
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20 x 2 LCD Driver? |
Posted: Sat Oct 13, 2018 9:07 am |
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Hello,
I bought few 20 x 2 LCD parallel displays and this is the information that I have:
1- Part number HC20216NYU-LYVO. This is the link for the Display and the datasheet: https://www.jameco.com/z/HC20216NYU-LYVO-Arndt-20-x-2-Black-And-Yellow-Parallel-LCD-Display-With-Green-Backlight_2155372.html
2- It uses the Samsung S6A006 series for driver and controller.
3- I found online the TheS6A0069 is made by Samsung and the HD44780 is made by Hitachi and they should be interchangeable?
I search the forum and my questions are:
1- Is there a CCS driver for this 20 x 2 LCD?
2- Can I drive it with 4 bit mode or do I need to use the standard 8 bit mode?
I did not connect it as of yet to any PIC until I get some answers to minimize trial and error I have good luck using 16 X 2 PCM programmer flex_lcd.c to drive several projects using the HD44780 LCD in 4 bit mode.
I would like to use this 20 x 2 LCD in one of my future projects as it has large characters.
Thank you, |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19520
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Posted: Sat Oct 13, 2018 11:05 am |
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The S6A0069 is a drop in replacement for the HD44780. Same instruction set and connections. Flex_LCD, should drive it directly. The display data sheet does not give the voltage levels needed for Vo, so you are going to need the pot on this, and to experiment to get the right display.
Displays like this always wake in 4-bit mode, and have to be set to 8bit by changing a register bit. Flex_LCD uses 4 bit mode. |
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temtronic
Joined: 01 Jul 2010 Posts: 9229 Location: Greensville,Ontario
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Posted: Sun Oct 14, 2018 5:23 am |
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hmm.. I was under the impression that the LCDs all defaulted to 8 bit mode so now I need to find a good datasheet.
I do remember driving one of a PC parallel port using QuickBASIC4.5....
have to admit that was, well, a long, long time ago......
Jay |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19520
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Posted: Sun Oct 14, 2018 5:55 am |
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Yes, apologies.
It actually wakes assuming 8bit, but you perform a double write of the setup register using 4bits only to change it. The standard setup sent by the Flex_LCD does this 'invisibly' and from then on it is 4bit.
Some of the third party equivalent chips do actually wake in 4bit mode. I've met one where a driver assumed it was in 8bit mode and it the equivalent chip then didn't work. |
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temtronic
Joined: 01 Jul 2010 Posts: 9229 Location: Greensville,Ontario
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Posted: Sun Oct 14, 2018 6:57 am |
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nice... so much for 'standards'... sigh.
Nice to know not all my grey cells are defunct. Sad thing is I cut that test code waiting for 'jury duty'....never got called, guess the pocket protector full of pens made me 'unacceptable' !
jay |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19520
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Posted: Sun Oct 14, 2018 10:47 am |
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Yes, I actually was 'caught' here by my memory of having problems with this display, assuming it was in 8bit mode, and instead having to explicitly set this, and then forgot that we had found 8bit was meant to be the default....
Most drivers start off be configuring the mode anyway. |
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Sam_40
Joined: 07 Jan 2015 Posts: 127
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Posted: Sun Oct 14, 2018 12:49 pm |
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I appreciate the inputs, one more question:
The driver for 2 X 16 will drive the 2 X 20?
I am going to assemble a board and will start my testing sometime next week.
Thanks |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19520
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Posted: Sun Oct 14, 2018 1:17 pm |
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Yes, it should work. |
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