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Replacing LCD trimpots for digital pots


Nomical

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A friend of mine sent me this site because it features digital potentiometers. At first i thought i probably wouldn't need them, but than i had an idea.

Why not connect the 3 pins/holes for the contrast control of the lcd to one of those digital pots (perhaps on a separate, small pcb).

They also have dual types, so you can connect both contrast and backlighting/luminescense to one dual digital pot.

My friend told me they had to be controlled by IIC (or is it IIS?) and TK has opened up some space in the PIC for that type of language recently, is it not?

So wouldn't it be possible to implement some extra code into the MIOS (if it isn't already there) or in the MIOS application to simply control this digital pot? It only has to have 2 inc/dec functions with a certain stepsize. Both could be controlled via the menu on the LCD. And that's what i would like to achieve for my project if possible.

What about the bankstick(s) if this IIC functionality is used? As far as i could find and understand in other topics, there will only be a limit on the transfer speed to the bankstick, right? And it's still possible to use the banksticks with all the functionalities they had except for the reduced speed? No harware changes?

Thanks

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A friend of mine sent me this site because it features digital potentiometers. At first i thought i probably wouldn't need them, but than i had an idea.

Why not connect the 3 pins/holes for the contrast control of the lcd to one of those digital pots (perhaps on a separate, small pcb).

They also have dual types, so you can connect both contrast and backlighting/luminescense to one dual digital pot.

My friend told me they had to be controlled by IIC (or is it IIS?) and TK has opened up some space in the PIC for that type of language recently, is it not?

So wouldn't it be possible to implement some extra code into the MIOS (if it isn't already there) or in the MIOS application to simply control this digital pot? It only has to have 2 inc/dec functions with a certain stepsize. Both could be controlled via the menu on the LCD. And that's what i would like to achieve for my project if possible.

What about the bankstick(s) if this IIC functionality is used? As far as i could find and understand in other topics, there will only be a limit on the transfer speed to the bankstick, right? And it's still possible to use the banksticks with all the functionalities they had except for the reduced speed? No harware changes?

Thanks

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See also http://www.midibox.org/cgi-bin/yabb/YaBB.cgi?board=mios;action=display;num=1061251988

The low level IIC driver is now open for applications (officially supported with MIOS V1.4, preliminary version available for download) and can be used to access other IIC devices. Sure, you can connect as much IIC devices as you want to CORE:J4, the transfers to the BankSticks are not affected.

The high-level driver for those digital pots has to be written by yourself (it's so easy like sending MIDI events) and will not be integrated into MIOS. Just write the code it into a .inc file so that it can be re-used in other applications.

Best Regards, Thorsten.

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See also http://www.midibox.org/cgi-bin/yabb/YaBB.cgi?board=mios;action=display;num=1061251988

The low level IIC driver is now open for applications (officially supported with MIOS V1.4, preliminary version available for download) and can be used to access other IIC devices. Sure, you can connect as much IIC devices as you want to CORE:J4, the transfers to the BankSticks are not affected.

The high-level driver for those digital pots has to be written by yourself (it's so easy like sending MIDI events) and will not be integrated into MIOS. Just write the code it into a .inc file so that it can be re-used in other applications.

Best Regards, Thorsten.

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That's very good news! ;D

I thought i read in the topic you posted some high transfer speed for the banksticks would be reduced, but apparantly there are no changes at all. :D

So i can connect 8 banksticks and use the IIC functions? That's very nice! Where should i connect the IIC interface (the digital pot), before or after the banksticks?

The driver is no problem, because i friend of mine can explain the IIC language and if it's that simple he will probably write it for me. As it has to be an .inc file, it will be included at the top of main.asm file in the mios application?  

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That's very good news! ;D

I thought i read in the topic you posted some high transfer speed for the banksticks would be reduced, but apparantly there are no changes at all. :D

So i can connect 8 banksticks and use the IIC functions? That's very nice! Where should i connect the IIC interface (the digital pot), before or after the banksticks?

The driver is no problem, because i friend of mine can explain the IIC language and if it's that simple he will probably write it for me. As it has to be an .inc file, it will be included at the top of main.asm file in the mios application?  

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