Hi All,

After getting my Timer_A to work correctly, I would now like to see
and make sure everything is working correctly by hooking up an LCD.
The mspgcc compiler has a nice sample for hooking up and running an
LCD. I purchased the LCD, got it wired up and nothing happens. Well,
I went back and looked at the LCD and it requires 5v to run.

I searched the archives and it looks like people are using a charge
pump to go from a battery (1.9v) to 3.3v but I can't find anything
where someone goes from 3.3v to 5v.

Any help would be greatly appreciated.

Have a great day,

Craig Start a New Thread

I use a MAX1677 to make 12V and switchable 3 or 5V from 2 D cells
(nominally 3V).

Emmett Redd Ph.D. mailto:E...@missouristate.edu
Professor (417)836-5221
Department of Physics, Astronomy, and Materials Science
Missouri State University Fax (417)836-6226
901 SOUTH NATIONAL Dept (417)836-5131
SPRINGFIELD, MO 65897 USA

A bad day doing research is better than a good day doing something else.

________________________________

From: m... [mailto:m...] On
Behalf Of Craig
Sent: Tuesday, December 12, 2006 10:57 AM
To: m...
Subject: [msp430] How to drive 5v LCD from 3.3v output?

Hi All,

After getting my Timer_A to work correctly, I would now like to
see
and make sure everything is working correctly by hooking up an
LCD.
The mspgcc compiler has a nice sample for hooking up and running
an
LCD. I purchased the LCD, got it wired up and nothing happens.
Well,
I went back and looked at the LCD and it requires 5v to run.

I searched the archives and it looks like people are using a
charge
pump to go from a battery (1.9v) to 3.3v but I can't find
anything
where someone goes from 3.3v to 5v.

Any help would be greatly appreciated.

Have a great day,

Craig Start a New Thread

You can use a charge pump to get 5 V. Texas has many.
Also you must take into account the logic voltages levels. Your msp has 3.3v
logic levels and if you power the lcd with 5 its logic levels will be 5. You
will need a level conversion IC.

_____

From: m... [mailto:m...] On Behalf Of
Craig
Sent: Martes, 12 de Diciembre de 2006 01:57 p.m.
To: m...
Subject: [msp430] How to drive 5v LCD from 3.3v output?

Hi All,

After getting my Timer_A to work correctly, I would now like to see
and make sure everything is working correctly by hooking up an LCD.
The mspgcc compiler has a nice sample for hooking up and running an
LCD. I purchased the LCD, got it wired up and nothing happens. Well,
I went back and looked at the LCD and it requires 5v to run.

I searched the archives and it looks like people are using a charge
pump to go from a battery (1.9v) to 3.3v but I can't find anything
where someone goes from 3.3v to 5v.

Any help would be greatly appreciated.

Have a great day,

Craig

--


--
Start a New Thread

I haven't yet found an LCD that won't oiperate with current limit
resistors in series from the 3V3 output of the micro. I generally use a
470R resistor.

Al

FB wrote:

>You can use a charge pump to get 5 V. Texas has many.
>Also you must take into account the logic voltages levels. Your msp has 3.3v
>logic levels and if you power the lcd with 5 its logic levels will be 5. You
>will need a level conversion IC.
>
> _____
>
>From: m... [mailto:m...] On Behalf Of
>Craig
>Sent: Martes, 12 de Diciembre de 2006 01:57 p.m.
>To: m...
>Subject: [msp430] How to drive 5v LCD from 3.3v output?
>
>Hi All,
>
>After getting my Timer_A to work correctly, I would now like to see
>and make sure everything is working correctly by hooking up an LCD.
>The mspgcc compiler has a nice sample for hooking up and running an
>LCD. I purchased the LCD, got it wired up and nothing happens. Well,
>I went back and looked at the LCD and it requires 5v to run.
>
>I searched the archives and it looks like people are using a charge
>pump to go from a battery (1.9v) to 3.3v but I can't find anything
>where someone goes from 3.3v to 5v.
>
>Any help would be greatly appreciated.
>
>Have a great day,
>
>Craig
>--
>
>
>
> Start a New Thread

MAX1595-50, ask for samples.

Al

Craig wrote:

>Hi All,
>
>After getting my Timer_A to work correctly, I would now like to see
>and make sure everything is working correctly by hooking up an LCD.
>The mspgcc compiler has a nice sample for hooking up and running an
>LCD. I purchased the LCD, got it wired up and nothing happens. Well,
>I went back and looked at the LCD and it requires 5v to run.
>
>I searched the archives and it looks like people are using a charge
>pump to go from a battery (1.9v) to 3.3v but I can't find anything
>where someone goes from 3.3v to 5v.
>
>Any help would be greatly appreciated.
>
>Have a great day,
>
>Craig
>Yahoo! Groups Links
>
>
> Start a New Thread

Hi Al,

I'm trying to use the following LCD controller,
http://www.sparkfun.com/datasheets/LCD/HD44780.pdf. It's the 2x16
display that Spark Fun sells.

The datasheet says it's needs a +5v. So, from your response, I can
just put a 470R resistor inline to the +5v on the LCD and be done
with it?

That would be great if I can just do that. Just in case though, I
ordered some sample of the MAX product too as indicated in your
response and one other response as well.

Thanks again guys for your help with this,

Craig

--- In m..., Onestone wrote:
>
> I haven't yet found an LCD that won't oiperate with current limit
> resistors in series from the 3V3 output of the micro. I generally
use a
> 470R resistor.
>
> Al
>
> FB wrote:
>
> >You can use a charge pump to get 5 V. Texas has many.
> >Also you must take into account the logic voltages levels. Your
msp has 3.3v
> >logic levels and if you power the lcd with 5 its logic levels
will be 5. You
> >will need a level conversion IC.
> >
> > _____
> >
> >From: m... [mailto:m...] On
Behalf Of
> >Craig
> >Sent: Martes, 12 de Diciembre de 2006 01:57 p.m.
> >To: m...
> >Subject: [msp430] How to drive 5v LCD from 3.3v output?
> >
> >
> >
> >Hi All,
> >
> >After getting my Timer_A to work correctly, I would now like to
see
> >and make sure everything is working correctly by hooking up an
LCD.
> >The mspgcc compiler has a nice sample for hooking up and running
an
> >LCD. I purchased the LCD, got it wired up and nothing happens.
Well,
> >I went back and looked at the LCD and it requires 5v to run.
> >
> >I searched the archives and it looks like people are using a
charge
> >pump to go from a battery (1.9v) to 3.3v but I can't find
anything
> >where someone goes from 3.3v to 5v.
> >
> >Any help would be greatly appreciated.
> >
> >Have a great day,
> >
> >Craig
> >
> >
> >
> >
> >
> >
> >--
> >No virus found in this incoming message.
> >Checked by AVG Free Edition.
> >Version: 7.1.409 / Virus Database: 268.15.16/582 - Release Date:
11/12/2006
> >
> >
> >
> >
> Start a New Thread

There are all kinds of LCDs ranging from bare-bone "glass" (liquid
crystal patterns sandwiched between two pieces of glass) to modules
with build-in VGA controllers.

The MSP430F4xx is capable of driving near bare-bone time-multiplexed
n-Row x m-Column LCD with a small number (~160) of segments. (Each
segment is usually a logo/icon, part of a "7-segment" digit, or part
of a "16-segment" character.)

For LCD modules with built-in controllers, you do not need this kind
of low-level capability. The controller does the multiplexing to a
lot more segments/dots/pixels as compared to F4xx. The controller
also generates all the needed voltages for the "glass". You use
parallel port, UART, I2C, or SPI to interface to this kind of LCD
modules. The MSP430 does not need to be F4xx. It can be F1xx or F2xx.
But if the LCD module needs 5V instead of 3V, you need another power
supply (not necessarily charge pump) and match the I/O levels (not
necessarily level converters).

--- In m..., "Craig" wrote:
>
> Hi Al,
>
> I'm trying to use the following LCD controller,
> http://www.sparkfun.com/datasheets/LCD/HD44780.pdf. It's the 2x16
> display that Spark Fun sells.
>
> The datasheet says it's needs a +5v. So, from your response, I can
> just put a 470R resistor inline to the +5v on the LCD and be done
> with it?
>
> That would be great if I can just do that. Just in case though, I
> ordered some sample of the MAX product too as indicated in your
> response and one other response as well.
>
> Thanks again guys for your help with this,
>
> Craig
>
> --- In m..., Onestone wrote:
> >
> > I haven't yet found an LCD that won't oiperate with current limit
> > resistors in series from the 3V3 output of the micro. I generally
> use a
> > 470R resistor.
> >
> > Al
> >
> > FB wrote:
> >
> > >You can use a charge pump to get 5 V. Texas has many.
> > >Also you must take into account the logic voltages levels. Your
> msp has 3.3v
> > >logic levels and if you power the lcd with 5 its logic levels
> will be 5. You
> > >will need a level conversion IC.
> > >
> > > _____
> > >
> > >From: m... [mailto:m...] On
> Behalf Of
> > >Craig
> > >Sent: Martes, 12 de Diciembre de 2006 01:57 p.m.
> > >To: m...
> > >Subject: [msp430] How to drive 5v LCD from 3.3v output?
> > >
> > >
> > >
> > >Hi All,
> > >
> > >After getting my Timer_A to work correctly, I would now like to
> see
> > >and make sure everything is working correctly by hooking up an
> LCD.
> > >The mspgcc compiler has a nice sample for hooking up and running
> an
> > >LCD. I purchased the LCD, got it wired up and nothing happens.
> Well,
> > >I went back and looked at the LCD and it requires 5v to run.
> > >
> > >I searched the archives and it looks like people are using a
> charge
> > >pump to go from a battery (1.9v) to 3.3v but I can't find
> anything
> > >where someone goes from 3.3v to 5v.
> > >
> > >Any help would be greatly appreciated.
> > >
> > >Have a great day,
> > >
> > >Craig
> > >
> > >
> > >
> > >
> > >
> > >
> > >--
> > >No virus found in this incoming message.
> > >Checked by AVG Free Edition.
> > >Version: 7.1.409 / Virus Database: 268.15.16/582 - Release Date:
> 11/12/2006
> > >
> > >
> > >
> > >
> > >
> Start a New Thread

Craig,
If you don't need to read the status or display ram, and output only to the lcd.. You can get away without level converters.. as long as you run the msp430 at least at 2.8v (most 430s are rated as high output = .8 x VCC).. I have used it many times at 3.0v

I use a charge pump to power the lcd and backlight.. I like the ltc1517-5

Craig wrote:
Hi Al,

I'm trying to use the following LCD controller,
http://www.sparkfun.com/datasheets/LCD/HD44780.pdf. It's the 2x16
display that Spark Fun sells.

The datasheet says it's needs a +5v. So, from your response, I can
just put a 470R resistor inline to the +5v on the LCD and be done
with it?

That would be great if I can just do that. Just in case though, I
ordered some sample of the MAX product too as indicated in your
response and one other response as well.

Thanks again guys for your help with this,

Craig

--- In m..., Onestone wrote:
>
> I haven't yet found an LCD that won't oiperate with current limit
> resistors in series from the 3V3 output of the micro. I generally
use a
> 470R resistor.
>
> Al
>
> FB wrote:
>
> >You can use a charge pump to get 5 V. Texas has many.
> >Also you must take into account the logic voltages levels. Your
msp has 3.3v
> >logic levels and if you power the lcd with 5 its logic levels
will be 5. You
> >will need a level conversion IC.
> >
> > _____
> >
> >From: m... [mailto:m...] On
Behalf Of
> >Craig
> >Sent: Martes, 12 de Diciembre de 2006 01:57 p.m.
> >To: m...
> >Subject: [msp430] How to drive 5v LCD from 3.3v output?
> >
> >
> >
> >Hi All,
> >
> >After getting my Timer_A to work correctly, I would now like to
see
> >and make sure everything is working correctly by hooking up an
LCD.
> >The mspgcc compiler has a nice sample for hooking up and running
an
> >LCD. I purchased the LCD, got it wired up and nothing happens.
Well,
> >I went back and looked at the LCD and it requires 5v to run.
> >
> >I searched the archives and it looks like people are using a
charge
> >pump to go from a battery (1.9v) to 3.3v but I can't find
anything
> >where someone goes from 3.3v to 5v.
> >
> >Any help would be greatly appreciated.
> >
> >Have a great day,
> >
> >Craig
> >
> >
> >
> >
> >
> >
> >--
> >No virus found in this incoming message.
> >Checked by AVG Free Edition.
> >Version: 7.1.409 / Virus Database: 268.15.16/582 - Release Date:
11/12/2006
> >
> >
> >
> >
> Start a New Thread

> *Subject:* [msp430] Re: How to drive 5v LCD from 3.3v output?
> *From:* "Craig"
> *To:* m...
> *Date:* Tue, 12 Dec 2006 20:38:52 -0000
>
> Hi Al,
>
> I'm trying to use the following LCD controller,
> http://www.sparkfun.com/datasheets/LCD/HD44780.pdf. It's the 2x16
> display that Spark Fun sells.
>
> The datasheet says it's needs a +5v. So, from your response, I can
> just put a 470R resistor inline to the +5v on the LCD and be done
> with it?

No - you need to distinguish between the power supply the display needs
to work, and the voltage levels you need to exchange with it.

1. You'll need to find or make 5V ( at least 4V6 or so ) from somewhere
to _power_ it ( or buy one that works at 3V3 ). But you'll probably find
it's very few mA, and any old hack will do it.

2. If you are only sending signals to it, and NEVER READING BACK you can
probably drive the signals straight from the MSP. It's outputs will go
very close to the 3V3 supply.... and the display will probably accept (
at the most demanding ) 2/3 of 5V as a logic 1. It MAY accept 2.4volts.
It's marginal, but for a demo, it'll probably work.

3. If you want to read data back you will get up to 5V out of the
display once you try to read from it. In theory, connecting 5V to an MSP
will blow it up. You can PROBABLY do it by sticking a high-value
resistor in between the two devices - there's a diode to 3V3 included in
the IO pin, and you can dump 1mA ( so about 2K resistor ) into it. In
the other direction a 2K resistor will probably not hinder your outgoing
signal.

The pukka way to do this is with a level-shifter IC. a Philips GTL2010
is the perfect object, but needs a couple of resistors and capacitors to
work. Bit fine to solder for an amateur.

74V1Gxx devices are pretty excellent for single signal, single
direction. They run off 3V3, and put up with 5V while powered on r off
perfectly ( the 74V1G66 doesn't quite hack it as you'd hope. )

I daresay someone can suggest a 74something245 to suit.

>
> That would be great if I can just do that. Just in case though, I
> ordered some sample of the MAX product too as indicated in your
> response and one other response as well.
>
> Thanks again guys for your help with this,
>
> Craig
>
> --- In m..., Onestone wrote:
> >
> > I haven't yet found an LCD that won't oiperate with current limit
> > resistors in series from the 3V3 output of the micro. I generally
> use a
> > 470R resistor.
> >
> > Al
> >
> > FB wrote:
> >
> > >You can use a charge pump to get 5 V. Texas has many.
> > >Also you must take into account the logic voltages levels. Your
> msp has 3.3v
> > >logic levels and if you power the lcd with 5 its logic levels
> will be 5. You
> > >will need a level conversion IC.
> > >
> > > _____
> > >
> > >From: m... [mailto:m...] On
> Behalf Of
> > >Craig
> > >Sent: Martes, 12 de Diciembre de 2006 01:57 p.m.
> > >To: m...
> > >Subject: [msp430] How to drive 5v LCD from 3.3v output?
> > >
> > >
> > >
> > >Hi All,
> > >
> > >After getting my Timer_A to work correctly, I would now like to
> see
> > >and make sure everything is working correctly by hooking up an
> LCD.
> > >The mspgcc compiler has a nice sample for hooking up and running
> an
> > >LCD. I purchased the LCD, got it wired up and nothing happens.
> Well,
> > >I went back and looked at the LCD and it requires 5v to run.
> > >
> > >I searched the archives and it looks like people are using a
> charge
> > >pump to go from a battery (1.9v) to 3.3v but I can't find
> anything
> > >where someone goes from 3.3v to 5v.
> > >
> > >Any help would be greatly appreciated.
> > >
> > >Have a great day,
> > >
> > >Craig
> > >
> > >
> > >
> > >
> > >
> > >
> > >--
> > >No virus found in this incoming message.
> > >Checked by AVG Free Edition.
> > >Version: 7.1.409 / Virus Database: 268.15.16/582 - Release Date:
> 11/12/2006
> > >
> > >
> > >
> > >
> > >
> >
> --
> *Included Files:*
> am2file:001-HTML_Message.html Start a New Thread

Hi David, you are correct, i'm using a character lcd 16x2 with a ms430f2011
direct connect, just writing values. It works perfectly. Good post.

regards

Breno

----- Original Message -----
From: "David Collier"
To:
Sent: Tuesday, December 12, 2006 8:55 PM
Subject: Re: [msp430] Re: How to drive 5v LCD from 3.3v output?
>
>> *Subject:* [msp430] Re: How to drive 5v LCD from 3.3v output?
>> *From:* "Craig"
>> *To:* m...
>> *Date:* Tue, 12 Dec 2006 20:38:52 -0000
>>
>> Hi Al,
>>
>> I'm trying to use the following LCD controller,
>> http://www.sparkfun.com/datasheets/LCD/HD44780.pdf. It's the 2x16
>> display that Spark Fun sells.
>>
>> The datasheet says it's needs a +5v. So, from your response, I can
>> just put a 470R resistor inline to the +5v on the LCD and be done
>> with it?
>
> No - you need to distinguish between the power supply the display needs
> to work, and the voltage levels you need to exchange with it.
>
> 1. You'll need to find or make 5V ( at least 4V6 or so ) from somewhere
> to _power_ it ( or buy one that works at 3V3 ). But you'll probably find
> it's very few mA, and any old hack will do it.
>
> 2. If you are only sending signals to it, and NEVER READING BACK you can
> probably drive the signals straight from the MSP. It's outputs will go
> very close to the 3V3 supply.... and the display will probably accept (
> at the most demanding ) 2/3 of 5V as a logic 1. It MAY accept 2.4volts.
> It's marginal, but for a demo, it'll probably work.
>
> 3. If you want to read data back you will get up to 5V out of the
> display once you try to read from it. In theory, connecting 5V to an MSP
> will blow it up. You can PROBABLY do it by sticking a high-value
> resistor in between the two devices - there's a diode to 3V3 included in
> the IO pin, and you can dump 1mA ( so about 2K resistor ) into it. In
> the other direction a 2K resistor will probably not hinder your outgoing
> signal.
>
> The pukka way to do this is with a level-shifter IC. a Philips GTL2010
> is the perfect object, but needs a couple of resistors and capacitors to
> work. Bit fine to solder for an amateur.
>
> 74V1Gxx devices are pretty excellent for single signal, single
> direction. They run off 3V3, and put up with 5V while powered on r off
> perfectly ( the 74V1G66 doesn't quite hack it as you'd hope. )
>
> I daresay someone can suggest a 74something245 to suit.
>
>>
>> That would be great if I can just do that. Just in case though, I
>> ordered some sample of the MAX product too as indicated in your
>> response and one other response as well.
>>
>> Thanks again guys for your help with this,
>>
>> Craig
>>
>> --- In m..., Onestone wrote:
>> >
>> > I haven't yet found an LCD that won't oiperate with current limit
>> > resistors in series from the 3V3 output of the micro. I generally
>> use a
>> > 470R resistor.
>> >
>> > Al
>> >
>> > FB wrote:
>> >
>> > >You can use a charge pump to get 5 V. Texas has many.
>> > >Also you must take into account the logic voltages levels. Your
>> msp has 3.3v
>> > >logic levels and if you power the lcd with 5 its logic levels
>> will be 5. You
>> > >will need a level conversion IC.
>> > >
>> > > _____
>> > >
>> > >From: m... [mailto:m...] On
>> Behalf Of
>> > >Craig
>> > >Sent: Martes, 12 de Diciembre de 2006 01:57 p.m.
>> > >To: m...
>> > >Subject: [msp430] How to drive 5v LCD from 3.3v output?
>> > >
>> > >
>> > >
>> > >Hi All,
>> > >
>> > >After getting my Timer_A to work correctly, I would now like to
>> see
>> > >and make sure everything is working correctly by hooking up an
>> LCD.
>> > >The mspgcc compiler has a nice sample for hooking up and running
>> an
>> > >LCD. I purchased the LCD, got it wired up and nothing happens.
>> Well,
>> > >I went back and looked at the LCD and it requires 5v to run.
>> > >
>> > >I searched the archives and it looks like people are using a
>> charge
>> > >pump to go from a battery (1.9v) to 3.3v but I can't find
>> anything
>> > >where someone goes from 3.3v to 5v.
>> > >
>> > >Any help would be greatly appreciated.
>> > >
>> > >Have a great day,
>> > >
>> > >Craig
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >
>> > >--
>> > >No virus found in this incoming message.
>> > >Checked by AVG Free Edition.
>> > >Version: 7.1.409 / Virus Database: 268.15.16/582 - Release Date:
>> 11/12/2006
>> > >
>> > >
>> > >
>> > >
>> > >
>> >
>> --
>> *Included Files:*
>> am2file:001-HTML_Message.html
>
> Yahoo! Groups Links

_______________________________________________________
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