Re: [Lcd4linux-devel] lcd4linux timings for Samsung 16x4 display

[Mattia Jona-L. <mat...@gm...>]

Hi Dennis. Hi Michael.

Did you try the lcd-linux driver for your display? It is a kernel
level driver for hd44780 displays and timings issues are quite well
under control.
If it really is a timings issue then lcd-linux might help.

http://lcd-linux.sourceforge.net/

Best

Mattia


On Tue, Mar 3, 2015 at 1:49 PM, Dennis Grant <re...@gm...> wrote:
> http://pdf1.alldatasheet.com/datasheet-pdf/view/105087/SAMSUNG/16T202DA1J.html
>
> Thanks Michael.
>
> I hope you are wrong about the voltage issue as that appears to be a
> nontrivial fix.
>
> My suspicion that it is timing is based on this:
>
> - With the original motherboard (GA-MA780G-UD3H) and processor (Phenom
> II x4 940) it worked fine.
> - Same motherboard, but upgraded processor (Phenom II x6 1090T) it
> mostly worked, but sections of the display that were being updated (eg
> CPU use) would occasionally shift right, then back (so CPU: 15% might
> read CPU: 155, then CPU: 205 etc - the "%" got overwritten at some
> point) This could be fixed by restarting the service
> - New motherboard + PCI parport card, same behavior, but now the
> second line vanishes after a while
>
> Note that I misspoke earlier; it is a 16x2
>
> What is maddening is that the display mounting points are slightly
> larger than what appears to be standard. I was going to replace it
> with a Matrix Orbital USB display, rather than buy a parport card, but
> the mounting holes are differently spaced.
>
> I guess we'll see.
>
> Thanks for the assist.
>
> DG
>
> On Tue, Mar 3, 2015 at 1:28 AM, Michael Reinelt <mi...@re...> wrote:
>> Hello Dennis,
>>
>> post a link to the datasheet, and your config, and I will have a look at it.
>>
>> Maybe its not a timing issue, but a voltage issue: Some display require 5V
>> signal level, and modern parports provide just 3.3V
>>
>> In this case you have to use a level shifter (e.g. 74HCT245)
>>
>> Am 2015-03-03 um 03:52 schrieb Dennis Grant:
>>>
>>> Hey there. I hope someone is still on this list.
>>>
>>> I have a display based on a Samsung 16T202DA1J 16x4 VFD. I have been
>>> using the HD44780 display driver with some success (every once and a
>>> while the display would overwrite a char to the left) but a recent
>>> motherboard upgrade and a change to a PCI based parport (yup, it is
>>> parport driven) has caused more problems.
>>>
>>> Given that is *almost* works - it's fine for a few minutes, then
>>> eventually corrupts - I think it is a timing issue.
>>>
>>> I have the datasheet PDF. Anybody feel like looking at it for me and
>>> telling me what timings I should be using?
>>>
>>> Thanks.
>>>
>>> DG
>>>
>>>
>>> ------------------------------------------------------------------------------
>>> Dive into the World of Parallel Programming The Go Parallel Website,
>>> sponsored
>>> by Intel and developed in partnership with Slashdot Media, is your hub for
>>> all
>>> things parallel software development, from weekly thought leadership blogs
>>> to
>>> news, videos, case studies, tutorials and more. Take a look and join the
>>> conversation now. http://goparallel.sourceforge.net/
>>> _______________________________________________
>>> Lcd4linux-devel mailing list
>>> Lcd...@li...
>>> https://lists.sourceforge.net/lists/listinfo/lcd4linux-devel
>>>
>>>
>>
>> --
>> Michael Reinelt <mi...@re...>
>> http://home.pages.at/reinelt
>> GPG-Key 0xDF13BA50
>> ICQ #288386781
>
> ------------------------------------------------------------------------------
> Dive into the World of Parallel Programming The Go Parallel Website, sponsored
> by Intel and developed in partnership with Slashdot Media, is your hub for all
> things parallel software development, from weekly thought leadership blogs to
> news, videos, case studies, tutorials and more. Take a look and join the
> conversation now. http://goparallel.sourceforge.net/
> _______________________________________________
> Lcd4linux-devel mailing list
> Lcd...@li...
> https://lists.sourceforge.net/lists/listinfo/lcd4linux-devel