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2005-11-16 by bhimanipankaj
Dear ARMieessss.. thanks for your replies , but my problem is I want to connect a 5V interface in traditional way that is 8 data lines and 3 control lines with LPC2214, now LPC2214 datasheet is saying that all GPIOs are 5V tolerant so I think I can connect the LCD with Pull Ups on GPIO pins or can I directly connect the 5V LCD with the port pins. Thanks Pankaj
2005-11-16 by Dan Beadle
Check the IO levels on the LCD and the minimum output high level on the 2114. The odds are good that you can directly connect the LCD to the '14 directly with no pull-ups. For example: the VOH min level on the 2148 is V3.3-0.4V or 2.9V MINIMUM... This is the lowest output that the LPC puts out for a standard load high. (Usually it will be closer to 3.3V) I am using a Lumex display with a Samsung controller. It has a VIH min of 2.2. Any input above 2.2 is guaranteed to be an input. Therefore, there is 2.9 - 2.2, or .7V of margin on the high side input to the LCD. On LOW, there is usually less of an issue. The LPC will guarantee that a zero is below VOL max 0.4V while the Samsung LCD controller requires input to be less than 0.6V, leaving a .2V margin. As for LCD to LPC... Here the Samsung can output .9 x Vcc or 4.5V max, but guarantees to put out at least 2.4V. The 2.4 is plenty to swing the LPC to high - it requires 2.0V or more. But if the input goes above 3.3V, the "5V Tolerant" feature of the LPC kicks in. I don't know the details, but generally, you can think of this as a resistor in series with the input, limiting current, and a protection diode that dumps the excessive voltage to the 3.3 rail. So.. Bottom line, with this LCD controller, you just wire it up (making sure to power the LCD from 5V) Hope this helps. Dan _____
From: lpc2000@yahoogroups.com [mailto:lpc2000@yahoogroups.com] On Behalf Of bhimanipankaj Sent: Tuesday, November 15, 2005 8:49 PM To: lpc2000@yahoogroups.com Subject: [lpc2000] LCD interface problem Dear ARMieessss.. thanks for your replies , but my problem is I want to connect a 5V interface in traditional way that is 8 data lines and 3 control lines with LPC2214, now LPC2214 datasheet is saying that all GPIOs are 5V tolerant so I think I can connect the LCD with Pull Ups on GPIO pins or can I directly connect the 5V LCD with the port pins. Thanks Pankaj SPONSORED LINKS Microprocessor <http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microprocessor&w2 =Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=9 3&.sig=tsVC-J9hJ5qyXg0WPR0l6g> Microcontrollers <http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microprocessor& w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s =93&.sig=DvJVNqC_pqRTm8Xq01nxwg> Pic microcontrollers <http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microproces sor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c =4&s=93&.sig=TpkoX4KofDJ7c6LyBvUqVQ> 8051 microprocessor <http://groups.yahoo.com/gads?t=ms&k=8051+microprocessor&w1=Microprocess or&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c= 4&s=93&.sig=1Ipf1Fjfbd_HVIlekkDP-A> _____ YAHOO! GROUPS LINKS * Visit your group "lpc2000 <http://groups.yahoo.com/group/lpc2000> " on the web. * To unsubscribe from this group, send an email to: lpc2000-unsubscribe@yahoogroups.com <mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe> * Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service <http://docs.yahoo.com/info/terms/> . _____ [Non-text portions of this message have been removed]
2005-11-16 by bhimanipankaj
Dear Dan, Thank you very much for explaning this tech info more technically. As it seems that now I am confident to connect 5V LCD directly to the lpc2214 as well as 2148. thanks again, any more queries i will definately ask u... Pankaj --- In lpc2000@yahoogroups.com, "Dan Beadle" <dan.beadle@i...> wrote:
> > Check the IO levels on the LCD and the minimum output high level on the > 2114. The odds are good that you can directly connect the LCD to the > '14 directly with no pull-ups. For example: > > the VOH min level on the 2148 is V3.3-0.4V or 2.9V MINIMUM... This is > the lowest output that the LPC puts out for a standard load high. > (Usually it will be closer to 3.3V) > > I am using a Lumex display with a Samsung controller. It has a VIH min > of 2.2. Any input above 2.2 is guaranteed to be an input. Therefore, > there is 2.9 - 2.2, or .7V of margin on the high side input to the LCD. > > On LOW, there is usually less of an issue. The LPC will guarantee that > a zero is below VOL max 0.4V while the Samsung LCD controller requires > input to be less than 0.6V, leaving a .2V margin. > > > As for LCD to LPC... > > Here the Samsung can output .9 x Vcc or 4.5V max, but guarantees to put > out at least 2.4V. The 2.4 is plenty to swing the LPC to high - it > requires 2.0V or more. But if the input goes above 3.3V, the "5V > Tolerant" feature of the LPC kicks in. I don't know the details, but > generally, you can think of this as a resistor in series with the input, > limiting current, and a protection diode that dumps the excessive > voltage to the 3.3 rail. > > So.. Bottom line, with this LCD controller, you just wire it up (making > sure to power the LCD from 5V) > > Hope this helps. > > Dan > > > _____ > > From: lpc2000@yahoogroups.com [mailto:lpc2000@yahoogroups.com] On Behalf > Of bhimanipankaj > Sent: Tuesday, November 15, 2005 8:49 PM > To: lpc2000@yahoogroups.com > Subject: [lpc2000] LCD interface problem > > > Dear ARMieessss.. > > thanks for your replies , but my problem is I want to connect a 5V > interface in traditional way that is 8 data lines and 3 control lines > with LPC2214, now LPC2214 datasheet is saying that all GPIOs are 5V > tolerant so I think I can connect the LCD with Pull Ups on GPIO pins > or can I directly connect the 5V LCD with the port pins. > > Thanks > > Pankaj > > > > > > > SPONSORED LINKS > Microprocessor > <http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microprocessor&w2 > =Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=9 > 3&.sig=tsVC-J9hJ5qyXg0WPR0l6g> Microcontrollers > <http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microprocessor& > w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s > =93&.sig=DvJVNqC_pqRTm8Xq01nxwg> Pic microcontrollers > <http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microproces > sor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c > =4&s=93&.sig=TpkoX4KofDJ7c6LyBvUqVQ> > 8051 microprocessor > <http://groups.yahoo.com/gads?t=ms&k=8051+microprocessor&w1=Microprocess > or&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c= > 4&s=93&.sig=1Ipf1Fjfbd_HVIlekkDP-A> > > _____ > > YAHOO! GROUPS LINKS > > > > * Visit your group "lpc2000 > <http://groups.yahoo.com/group/lpc2000> " on the web. > > * To unsubscribe from this group, send an email to: > lpc2000-unsubscribe@yahoogroups.com > <mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe> > > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of > Service <http://docs.yahoo.com/info/terms/> . > > > _____ > > > > > [Non-text portions of this message have been removed] >
2005-11-16 by bhimanipankaj
Dear all, If I am connecting 5V lcd directly with lpc2214, should I common all the grounds for 5V for LCD supply as well as 3.3V for controller supply. Pankaj --- In lpc2000@yahoogroups.com, "Dan Beadle" <dan.beadle@i...> wrote:
> > Check the IO levels on the LCD and the minimum output high level on the > 2114. The odds are good that you can directly connect the LCD to the > '14 directly with no pull-ups. For example: > > the VOH min level on the 2148 is V3.3-0.4V or 2.9V MINIMUM... This is > the lowest output that the LPC puts out for a standard load high. > (Usually it will be closer to 3.3V) > > I am using a Lumex display with a Samsung controller. It has a VIH min > of 2.2. Any input above 2.2 is guaranteed to be an input. Therefore, > there is 2.9 - 2.2, or .7V of margin on the high side input to the LCD. > > On LOW, there is usually less of an issue. The LPC will guarantee that > a zero is below VOL max 0.4V while the Samsung LCD controller requires > input to be less than 0.6V, leaving a .2V margin. > > > As for LCD to LPC... > > Here the Samsung can output .9 x Vcc or 4.5V max, but guarantees to put > out at least 2.4V. The 2.4 is plenty to swing the LPC to high - it > requires 2.0V or more. But if the input goes above 3.3V, the "5V > Tolerant" feature of the LPC kicks in. I don't know the details, but > generally, you can think of this as a resistor in series with the input, > limiting current, and a protection diode that dumps the excessive > voltage to the 3.3 rail. > > So.. Bottom line, with this LCD controller, you just wire it up (making > sure to power the LCD from 5V) > > Hope this helps. > > Dan > > > _____ > > From: lpc2000@yahoogroups.com [mailto:lpc2000@yahoogroups.com] On Behalf > Of bhimanipankaj > Sent: Tuesday, November 15, 2005 8:49 PM > To: lpc2000@yahoogroups.com > Subject: [lpc2000] LCD interface problem > > > Dear ARMieessss.. > > thanks for your replies , but my problem is I want to connect a 5V > interface in traditional way that is 8 data lines and 3 control lines > with LPC2214, now LPC2214 datasheet is saying that all GPIOs are 5V > tolerant so I think I can connect the LCD with Pull Ups on GPIO pins > or can I directly connect the 5V LCD with the port pins. > > Thanks > > Pankaj > > > > > > > SPONSORED LINKS > Microprocessor > <http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microprocessor&w2 > =Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=9 > 3&.sig=tsVC-J9hJ5qyXg0WPR0l6g> Microcontrollers > <http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microprocessor& > w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s > =93&.sig=DvJVNqC_pqRTm8Xq01nxwg> Pic microcontrollers > <http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microproces > sor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c > =4&s=93&.sig=TpkoX4KofDJ7c6LyBvUqVQ> > 8051 microprocessor > <http://groups.yahoo.com/gads?t=ms&k=8051+microprocessor&w1=Microprocess > or&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c= > 4&s=93&.sig=1Ipf1Fjfbd_HVIlekkDP-A> > > _____ > > YAHOO! GROUPS LINKS > > > > * Visit your group "lpc2000 > <http://groups.yahoo.com/group/lpc2000> " on the web. > > * To unsubscribe from this group, send an email to: > lpc2000-unsubscribe@yahoogroups.com > <mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe> > > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of > Service <http://docs.yahoo.com/info/terms/> . > > > _____ > > > > > [Non-text portions of this message have been removed] >
2005-11-16 by Ake Hedman, eurosource
Yes. You have to have a common ground. /Ake bhimanipankaj wrote: > Dear all, > > If I am connecting 5V lcd directly with lpc2214, should I common all > the grounds for 5V for LCD supply as well as 3.3V for controller supply. > > Pankaj > > --- In lpc2000@yahoogroups.com, "Dan Beadle" <dan.beadle@i...> wrote: > > > > Check the IO levels on the LCD and the minimum output high level on the > > 2114. The odds are good that you can directly connect the LCD to the > > '14 directly with no pull-ups. For example: > > > > the VOH min level on the 2148 is V3.3-0.4V or 2.9V MINIMUM... This is > > the lowest output that the LPC puts out for a standard load high. > > (Usually it will be closer to 3.3V) > > > > I am using a Lumex display with a Samsung controller. It has a VIH min > > of 2.2. Any input above 2.2 is guaranteed to be an input. Therefore, > > there is 2.9 - 2.2, or .7V of margin on the high side input to the LCD. > > > > On LOW, there is usually less of an issue. The LPC will guarantee that > > a zero is below VOL max 0.4V while the Samsung LCD controller requires > > input to be less than 0.6V, leaving a .2V margin. > > > > > > As for LCD to LPC... > > > > Here the Samsung can output .9 x Vcc or 4.5V max, but guarantees to put > > out at least 2.4V. The 2.4 is plenty to swing the LPC to high - it > > requires 2.0V or more. But if the input goes above 3.3V, the "5V > > Tolerant" feature of the LPC kicks in. I don't know the details, but > > generally, you can think of this as a resistor in series with the input, > > limiting current, and a protection diode that dumps the excessive > > voltage to the 3.3 rail. > > > > So.. Bottom line, with this LCD controller, you just wire it up (making > > sure to power the LCD from 5V) > > > > Hope this helps. > > > > Dan > > > > > > _____ > > > > From: lpc2000@yahoogroups.com [mailto:lpc2000@yahoogroups.com] On Behalf > > Of bhimanipankaj > > Sent: Tuesday, November 15, 2005 8:49 PM > > To: lpc2000@yahoogroups.com > > Subject: [lpc2000] LCD interface problem > > > > > > Dear ARMieessss.. > > > > thanks for your replies , but my problem is I want to connect a 5V > > interface in traditional way that is 8 data lines and 3 control lines > > with LPC2214, now LPC2214 datasheet is saying that all GPIOs are 5V > > tolerant so I think I can connect the LCD with Pull Ups on GPIO pins > > or can I directly connect the 5V LCD with the port pins. > > > > Thanks > > > > Pankaj > > > > > > > > > > > > > > SPONSORED LINKS > > Microprocessor > > > <http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microprocessor&w2 > <http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microprocessor&w2> > > =Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=9 > > 3&.sig=tsVC-J9hJ5qyXg0WPR0l6g> Microcontrollers > > > <http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microprocessor& > <http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microprocessor&> > > w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s > > =93&.sig=DvJVNqC_pqRTm8Xq01nxwg> Pic microcontrollers > > > <http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microproces > <http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microproces> > > sor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c > > =4&s=93&.sig=TpkoX4KofDJ7c6LyBvUqVQ> > > 8051 microprocessor > > > <http://groups.yahoo.com/gads?t=ms&k=8051+microprocessor&w1=Microprocess > <http://groups.yahoo.com/gads?t=ms&k=8051+microprocessor&w1=Microprocess> > > or&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c= > > 4&s=93&.sig=1Ipf1Fjfbd_HVIlekkDP-A> > > > > _____ > > > > YAHOO! GROUPS LINKS > > > > > > > > * Visit your group "lpc2000 > > <http://groups.yahoo.com/group/lpc2000> " on the web. > > > > * To unsubscribe from this group, send an email to: > > lpc2000-unsubscribe@yahoogroups.com > > <mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe> > > > > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of > > Service <http://docs.yahoo.com/info/terms/> . > > > > > > _____ > > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > SPONSORED LINKS > Microprocessor > <http://groups.yahoo.com/gads?t=ms&k=Microprocessor&w1=Microprocessor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=93&.sig=tsVC-J9hJ5qyXg0WPR0l6g> > Microcontrollers > <http://groups.yahoo.com/gads?t=ms&k=Microcontrollers&w1=Microprocessor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=93&.sig=DvJVNqC_pqRTm8Xq01nxwg> > Pic microcontrollers > <http://groups.yahoo.com/gads?t=ms&k=Pic+microcontrollers&w1=Microprocessor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=93&.sig=TpkoX4KofDJ7c6LyBvUqVQ> > > 8051 microprocessor > <http://groups.yahoo.com/gads?t=ms&k=8051+microprocessor&w1=Microprocessor&w2=Microcontrollers&w3=Pic+microcontrollers&w4=8051+microprocessor&c=4&s=93&.sig=1Ipf1Fjfbd_HVIlekkDP-A> > > > > ------------------------------------------------------------------------ > YAHOO! GROUPS LINKS > > * Visit your group "lpc2000 > <http://groups.yahoo.com/group/lpc2000>" on the web. > > * To unsubscribe from this group, send an email to: > lpc2000-unsubscribe@yahoogroups.com > <mailto:lpc2000-unsubscribe@yahoogroups.com?subject=Unsubscribe> > > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of > Service <http://docs.yahoo.com/info/terms/>. > > > ------------------------------------------------------------------------ > -- --- Ake Hedman (YAP - Yet Another Programmer) eurosource, Brattbergavägen 17, 820 50 LOS, Sweden Phone: (46) 657 413430 Cellular: (46) 73 84 84 102 Company home: http://www.eurosource.se Kryddor/Te/Kaffe: http://www.brattberg.com Personal homepage: http://www.eurosource.se/akhe Automated home: http://www.vscp.org [Non-text portions of this message have been removed]