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LCD display with UC1601 experience

Started by Boris Kralik February 2, 2006
Hello.
Do you have anybody experience with LCD display with UltraChip
controller ?
I want to operate with this using SPI, but commands not working. I
power LCD with 3V (Vdd), 5V (Vlcd) and working in S9 mode with 3 wire
connections. I try any command send to LCD, but any reply.
If anybody have source code of procedure for control this, it help me.
Thanks.
	

An Engineer's Guide to the LPC2100 Series

Boris,

First double-check the pinout. It's "mother" of about 99% of all
mistakes-

Second, check timing. I finished one SPI LCD driver last week and used 
LPC2138 SPP with max. clock. It was too fast for the LCD and I need to 
reduce clock frequency to operate properly.

Marko

Boris Kralik wrote:

> Hello.
> Do you have anybody experience with LCD display with UltraChip
> controller ?
> I want to operate with this using SPI, but commands not working. I
> power LCD with 3V (Vdd), 5V (Vlcd) and working in S9 mode with 3 wire
> connections. I try any command send to LCD, but any reply.
> If anybody have source code of procedure for control this, it help me.
> Thanks.
>
>
	
Hi Marko.
I check pinout one more time, pinout is good (I think:
Vdd=3V, Vlcd=5V(with capacitors), CS0=pullup to H,
PS1=pullup to H, CD to uProc,  PS0 to
GND;D1,3,4,5,6,7,RD/WR=GND; Vlcd -> Cap 1uF, and other
pins (VB0+,-; VB1+,-) about LCD with capacitors 1uF)).
I change Vlcd, first was 3V (same as Vdd) and I
changed to 5V. Power consumation increase from cca.
30mA to 110mA. I think, this is good, manual says
2x60mA. Timing I check on scope, minimal timming at UC
is in nano seconds, I work with micro sec.
When I check pin VB0+,VB0-; VB1+, VB1- with scope without signal, but not
connect to GND. 
Question: It is good ? I think not !!!
Please check your signal on VC pins.
Thank for you advise.

--- "Marko Pavlin (home)" <mp@mp@....> wrote:

> Boris,
> 
> First double-check the pinout. It's "mother" of
> about 99% of all mistakes-
> 
> Second, check timing. I finished one SPI LCD driver
> last week and used 
> LPC2138 SPP with max. clock. It was too fast for the
> LCD and I need to 
> reduce clock frequency to operate properly.
> 
> Marko
> 
> Boris Kralik wrote:
> 
> > Hello.
> > Do you have anybody experience with LCD display
> with UltraChip
> > controller ?
> > I want to operate with this using SPI, but
> commands not working. I
> > power LCD with 3V (Vdd), 5V (Vlcd) and working in
> S9 mode with 3 wire
> > connections. I try any command send to LCD, but
> any reply.
> > If anybody have source code of procedure for
> control this, it help me.
> > Thanks.
> >
> >
> 
>
	Regards / S pozdravom Boris Kralik

http://www.geocities.com/kralikbo/
-------------
	___________________________________________________________ 
NEW Yahoo! Cars - sell your car and browse thousands of new and used cars
online! http://uk.cars.yahoo.com/

Boris Krik wrote:

>Hi Marko.
>I check pinout one more time, pinout is good (I think:
>Vdd=3V, Vlcd=5V(with capacitors), CS0=pullup to H,
>PS1=pullup to H, CD to uProc,  PS0 to
>GND;D1,3,4,5,6,7,RD/WR=GND; Vlcd -> Cap 1uF, and other
>pins (VB0+,-; VB1+,-) about LCD with capacitors 1uF)).
>I change Vlcd, first was 3V (same as Vdd) and I
>changed to 5V. Power consumation increase from cca.
>30mA to 110mA. I think, this is good, manual says
>2x60mA. Timing I check on scope, minimal timming at UC
>is in nano seconds, I work with micro sec.
>When I check pin VB0+,VB0-; VB1+, VB1- with scope >without signal, but
not connect to GND. 
>Question: It is good ? I think not !!!
>Please check your signal on VC pins.
>Thank for you advise.
>
>  
>
If you have a scope, then the problem can be quickly traced down.  I 
would start out by verifying my understanding of the LCD controller 
registers.  For example, LCD have a number of parameters which need to 
be matched up against the display: dot-clock rate, lines per frame, 
frame rate, etc.

I would start out by calculating what the dot clock rate would be needed 
for the display.  Check the dot clock spec of the LCD spec.  Then see if 
you can program the controller to that dot frequency and verify on the 
scope.

Next is the number of dots per line.  Calculate dot-clock X number 
pixels per line.  This would give you the time interval of the Line 
Pulse (latch).  Verify that the Line Pulse rate is what is called out 
for in the LCD data sheet.

Next, calculate the Frame Pulse rate: dot-clock X number_pixels_per_line 
X number_of_lines.  Check the this time against what you see on the scope.

Finally, check the data line feeding the display, you should see 
constant data flowing out the LCD.  Assuming of course that you've put 
some data into the DMA / Frame buffer of the LCD controller?

Try clearing the LCD Frame buffer of data (all zeros), look at the data 
pulses going to the display. Then, fill the LCD Frame buffer with ones, 
did the data stream change dramatically?

If all the above are correct and reasonable values (+/- 10%) then take a 
real hard look at the electronics.  Many LCD displays will require a 
specific power on sequencing of the power supply to them.  If you 
violate this powerup sequence you run the risk of "freezing" the 
crystals within the display and they will not move for you.

An LCD is a dynamic device.  The crystals are in constant motion, think 
of it as an acrobat doing cartwheels.  if you hold these crystals into a 
single for too long, or jam them into position, they will freeze in place.
	I've always found that if I cannot find out what is "wrong",
prove what 
is "right".

Regards,

TomW
	-- 
Tom Walsh - WN3L - Embedded Systems Consultant
http://openhardware.net, http://cyberiansoftware.com
"Windows? No thanks, I have work to do..."
----------------
	
Boris Krik wrote:

>Hi Marko.
>I check pinout one more time, pinout is good (I think:
>Vdd=3V, Vlcd=5V(with capacitors), CS0=pullup to H,
>PS1=pullup to H, CD to uProc,  PS0 to
>GND;D1,3,4,5,6,7,RD/WR=GND; Vlcd -> Cap 1uF, and other
>pins (VB0+,-; VB1+,-) about LCD with capacitors 1uF)).
>I change Vlcd, first was 3V (same as Vdd) and I
>changed to 5V. Power consumation increase from cca.
>30mA to 110mA. I think, this is good, manual says
>2x60mA. Timing I check on scope, minimal timming at UC
>is in nano seconds, I work with micro sec.
>  
>

Not sure what you meant by "minimal timing is UC is in nano seconds, I 
work with micro seconds".  You cannot run an LCD at a frequency 
significantly higher or lower than what is called for in the data 
sheet.  The timing is fairly strict.

Regards,

TomW

-- 
Tom Walsh - WN3L - Embedded Systems Consultant
http://openhardware.net, http://cyberiansoftware.com
"Windows? No thanks, I have work to do..."
----------------
	
OK Tom.
US = (us)micro second:sorry for my key mistake :-) .
Manual BTHQ12806, page 11 says in units ns (nano seconds), maximal
'tCY80' value is 135 ns and more. Maximal timing vlaue is not
exsistent. My time is in u(mikro)s, higher value; clk(CLK) and
clka(SDA) too. I check my values, it is in 'us' and 'tahs8'
(time to
change CS) was higher as 40ns(manual says), my value is in 'us',
frequency SCK is lower as manual says.
Next (tomorrow, I am at home :-)) I check pinout ones more time, but
I0mA is more (I think).
Direction:current value is good ?
Thanks for you seats.

--- In lpc2000@lpc2..., Tom Walsh <tom@...> wrote:
>
> Boris Krik wrote:
> 
> >Hi Marko.
> >I check pinout one more time, pinout is good (I think:
> >Vdd=3V, Vlcd=5V(with capacitors), CS0=pullup to H,
> >PS1=pullup to H, CD to uProc,  PS0 to
> >GND;D1,3,4,5,6,7,RD/WR=GND; Vlcd -> Cap 1uF, and other
> >pins (VB0+,-; VB1+,-) about LCD with capacitors 1uF)).
> >I change Vlcd, first was 3V (same as Vdd) and I
> >changed to 5V. Power consumation increase from cca.
> >30mA to 110mA. I think, this is good, manual says
> >2x60mA. Timing I check on scope, minimal timming at UC
> >is in nano seconds, I work with micro sec.
> >  
> >
> 
> Not sure what you meant by "minimal timing is UC is in nano seconds, I

> work with micro seconds".  You cannot run an LCD at a frequency 
> significantly higher or lower than what is called for in the data 
> sheet.  The timing is fairly strict.
> 
> Regards,
> 
> TomW
> 
> -- 
> Tom Walsh - WN3L - Embedded Systems Consultant
> http://openhardware.net, http://cyberiansoftware.com
> "Windows? No thanks, I have work to do..."
> ----------------
>
	

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