Incorrect Speed? LCD2041

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

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mcowger
LCD?
Posts: 3
Joined: Thu Apr 08, 2010 10:19 pm

Incorrect Speed? LCD2041

Post by mcowger »

I appear to have what I think is a defective LCD....I've got it hooked up to an Arduino, giving it regulated 5VDC and am sending at 19200 (with the RS232 jumpers unset and the TTL jumpers set), but all I get is noise when I send characters. I'm very confident the Arduino is working, as I wrote a test program to have it loop back to itself, and thats all working fine. it very much feels like the LCD is timing itself @ something other than 19200....although I've also tried sending at all speeds the LCD supports.

uProject isn't an option for me, as I dont have a serial port (nor a windows machine).

Anything else I can try before I decide the board is faulty and go buy a new one?

--M

Raquel
Matrix Orbital
Matrix Orbital
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Post by Raquel »

Hi,

Thank you for posting on the forum.

Try the following out:
1. Install manual override on the display. Please see Section 2.5 of the
manual. Cycle the power and leave this jump on. See if this fixes the problem.

2. Try swapping the RX and TX lines.

I hope these help. Let me know how it turns out.
Raquel Malinis
Design and Development
Matrix Orbital

mcowger
LCD?
Posts: 3
Joined: Thu Apr 08, 2010 10:19 pm

Post by mcowger »

Thanks Raquel,

I tried both your suggestions, and neither helped.

The reset jumper didn't fix the issue and swapping the tx/rx lines resulted in the display displaying nothing (as I would expect).

Is there an RMA process?

Clark
Matrix Orbital
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Post by Clark »

Hi M,

If you fire an email over to support@matrixorbital.ca with the serial number, problem description, shipping info, and a contact number I can get you started on the RMA process.

However, just to make sure we have all the bases covered, please check your communication protocol against that of the display. It will expect 8N1; 8 bits data, no parity, and one bit stop. Flow control must be off and there are no start bits. Communication levels at TTL are 3-5.5V high, -0.2-1V low. If you are still having trouble, please feel free to contact me for an RMA.

Thanks,
~Troy
Troy Clark
Design & Development
Matrix Orbital

mcowger
LCD?
Posts: 3
Joined: Thu Apr 08, 2010 10:19 pm

Post by mcowger »

THanks Troy,

I have confirmed those values - the Arduino actually has no real way to set anything besides 8N1 (unless one fiddles with various registers). I'm also using TTL logic of 0V low and 4.92V high.

I'll send you an email.

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