LVPK162-12 doesn't show anything but the MO startup screen

LK/ELK/VK/PK/OK/MX/GLK/EGLK/GVK/GLT Series

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maravape
LCD?
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Joined: Sat Sep 30, 2006 11:31 am

LVPK162-12 doesn't show anything but the MO startup screen

Post by maravape »

LVPK162-12 PCB R3.0 doesn't display anything but the Matrix Orbital start up screen, I'm working with a PIC18F4550 and the I2C protocol...

I took out all three jumpers from the 232 section, soldered two of them on the I2C section and the third one I soldered it in the Power through db9 section... the conexions are ok, I've checked them several times with a tester... I've add a 10K pull up resistor to the SDA line and another one to the SCL line.

The I2C program that I wrote for the PIC18F4550 works fine when I use it with a I2C serial EEPROM at 100KHz... But when I change the SSPADD for 400 KHz to comunicate with the LCD and when I send Start bit / 0x50 I don't recieve an ACK from the LCD. I thought the address was changed so I shortcircuited pins 3 and 4 with a shunt and see if I'd recieved an ACK from the LCD but didn't work... The program uses a 3 second delay before atempt to comunicate with the LCD...

The PIC18F4550 is working at 32 MHz (using a 4MHz christal and the PLL/3 feature)...

By the way sory for my poor english, do you speak spanish? if so, is it ok if we'd wrote in spanish?

Thanks
Last edited by maravape on Mon Oct 02, 2006 11:07 am, edited 1 time in total.
Marvin Valencia

maravape
LCD?
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Joined: Sat Sep 30, 2006 11:31 am

Re: LVPK162-12 doesn't show anything but the MO startup scre

Post by maravape »

If somebody from Matrix Orbital read this I think it's very important to read very carefully the LK162-12 Technical Manual Revision: 3.0

I think I found a bug on the manual... On page 7 the figure 11 (RS-232 Pin out) says that Pin 2 is SCL and that Pin 3 is SDA... now please check out figure 13 (Power Data connector and pin out) at page 8... it says that Pin 2 is SCL and that Pin 3 is SDA... now with a tester check that pin 2 from db9 is shortcircuited with Pin 3 from the Power Data Connector... so it means that "SCL from db9" is shortcircuited with SDA from the power data connector... same way check with the tester and you'll find out that "SDA from db9" is shortcircuited with SCL from the power data connector...

My project wasn't working because its hardware was designed based on the pinout from figure 11... but as soon as I found out about this bug I switch SCL and SDA lines from the db9 connector... And guess what... It worked just fine...!!! It seems that the pinout of figure 11 is wrong...!!!

Now please say something about this bug, I'll be waiting for your answer and waiting for you to change your manual figures... I can't complain about MO tech support team because I found a solution like two hours after I wrote the first msg about my project's issue and I think that's a very little time for you to replay it because I think you must have a lot of questions to answer from a lot of people...

Best regards...
Last edited by maravape on Mon Oct 02, 2006 11:11 am, edited 1 time in total.
Marvin Valencia

Raquel
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Post by Raquel »

Hello Marvin,

Thank you for posting on the forum.

Thank you also for pointing the DB9 pin outs. The technical writer is correcting the information now.

Best Regards,
Raquel Malinis
Design and Development
Matrix Orbital

Jon
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Post by Jon »

Hi Marvin,

Thanks for posting! While I am sorry to hear about the trouble that this has caused you, I am glad that we now have the oportunity to fix this issue so that other people may benifit, thank you for your contribution.

Now all that's left for me to do is to go through the manuals and update this!

--
Jon

maravape
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Joined: Sat Sep 30, 2006 11:31 am

Post by maravape »

I'm glad I can help...!!!
Marvin Valencia

ghost2501
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Re:

Post by ghost2501 »

Jon wrote:Hi Marvin,

Thanks for posting! While I am sorry to hear about the trouble that this has caused you, I am glad that we now have the oportunity to fix this issue so that other people may benifit, thank you for your contribution.

Now all that's left for me to do is to go through the manuals and update this!

--
Jon
Hello jon,

So I have a LK162-12 r2.220 It seems the manual for it also has the wrong pinouts like stated above. Maybe you should have changed the other manuals and not just the r3 manual because i basically spent the last 6 months learning arduino and trying to get this display to work all with no success and somewhere in between my display went haywire. I have been a avid fan of MO since i saw it on screen savers probably over 10 years ago and bought over 20 displays over the years, mostly used but several mx new ones.

In short if you read my other thread and weren't depressed enough jump over to the arduino forums and see my posts over there thinking it was arduino code at fault, meanwhile I wonder if that mistake in the manual.... one of several i found myself....... caused me to waste all this time and now BRICKED my display...?

http://www.lcdforums.com/forums/viewtop ... f=1&t=5782

Clark
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Re: LVPK162-12 doesn't show anything but the MO startup scre

Post by Clark »

Hello Ghost,

Please find the correct pinout for the DB9 and 4pin connectors of the LK162-12 Rev2.20 below. Configurations for different protocols are shown on pages 13, 14, and 15 of the manual.

DB9 - 4pin - LCD - Host - I2C
--2-----3------Tx----Rx----SDA
--3-----2------Rx----Tx----SCL

Swapping SCL and SDA connections will not damage a display, but it is definitely an annoyance and I do apologize for the error.

Thanks,
Troy
Troy Clark
Design & Development
Matrix Orbital

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