GLK240128-25 lost RS232 comm & can't back to factory def

philyang · Post by **philyang** » Thu Oct 30, 2008 1:13 pm

I have just received a GLK240128-25-GW. It works fine until my PC sent some random data into it.

By jumping R5 and C1, I can recover Contrast (128) and Backlight (255), but I could not make Baud Rate set at 19200kbps after power up. Following is my operation.

1. Jump R5 and C1.
2. Power on.
3. Draw a line to ensure factory settings (19200kbps). I could draw a line.
4. Send 254 57 0x67 to LCD.
5. Power off.
6. Remove jumper for R5 and C1.
7. Power on again.
8. My PC could not tlak to GLK240128-25-GW with 19200kbps.
9. Tries other baud settings, no one could work.

On page 18 of manual GLK240128-25-Q: The display
module can be manually reset to 19,200 baud in the event of an error
during transmission, including transmitting a value not listed below, by
setting the manual override jumper on the display module controller
board during power up. This command is ignored until this jumper is
removed again.

With some changes from previous operation procedure as below
......
4. Remove jumper for R5 and C1.
5. Send 254 57 0x67 to LCD.
6. Power off.
......

Same thing. It seems I completely lost RS232 communication at power up. How can I go back to factory settings completely?

Thank you for your time and help,

Phillip Yang

Post by **Ray** » Thu Oct 30, 2008 2:05 pm

Just to rule out any errors in your code, could you try resetting the baudrate using mogd# when the jumper is on?

philyang · Post by **philyang** » Thu Oct 30, 2008 3:08 pm

I used Mogsharp to test and still not work.

1. With jump on, dirrectly selecting 115200 from Spped box.
2. Can not draw a line.
3. Change back to 19200, can draw a line.
4. From Configure Display Defaults, select 115200 from New Baudrate and click Change. Baudrate in Speed box changed as well.
5. Can draw a line.
6. Change back 19200.
7. Click write. (do not know if neccesary)
8. Power off.
9. Remove jumper.
10. Power on.
11. Still no communication.

It seems only with jump on, LCD can work in 19200kbps.

Raquel · Post by **Raquel** » Thu Oct 30, 2008 3:19 pm

Hello,

Sorry about the problem you are having.

I wonder, if you please send the display (when you can communicate with it, ie with a jump on at 19200) the command 254 / 208. This will make the display spit back about 400 bytes of data.

Please email me these data at mo@matrixorbital.ca.

You can use uProject to do this, by going to Uploader tab, and go to Commands, Add, Raw Data and type in /254//208/ in the Raw Data line. Click Ok on the Add Raw Data window and then hit F9, Enter (this executes the command and you should see the bytes sent back by the display). Copy and paste the bytes and email them to me.

Thanks,

Raquel · Post by **Raquel** » Thu Oct 30, 2008 4:15 pm

Thanks for the data, Phil.

It seems that your EEPROM has been unintentionally written. I see that Data Lock parameter (please see section 12.1 of the manual) has been locked.

Again, while you have communication with the display, send the commands:
/254//203//245//160//0/ - this unlocks all levels of data lock
/254//57//103// - sets the baud rate to 19200

Remove the jumper and cycle the power. Check if 19200 sticks.

Please let me know how it turns out.

philyang · Post by **philyang** » Fri Oct 31, 2008 8:45 am

Hi Raquel,

It works now. I suspected the data was locked and ever used /254//202//0/ to unlock display, but I really could not think up the command /254//203//245//160//0/ from the section 12.1 of the manual.

Thanks a lot for the help and time.

Phillip Yang

Clark · Post by **Clark** » Mon Nov 03, 2008 11:42 am

Hi Phillip,

I've had a look at your post, as well as the manual, and have now updated the command and a few others in a new copy of the document.

~Troy