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vk5la
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Joined: 05/03/2017
Location: Australia
Posts: 13

Posted: 02:47am 17 Jan 2019

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Hi all,
after obtaining a pickit3 clone I thought I would have a go at upgrading the firmware on my Micromite Plus 64 pin backpack board (A couple of years old via Silicon Chip)
Previous to this upgrade, it was working 100%, including touch.
After the upgrade (which went 100% fine, no errors reported and I'm able to connect to the board via a serial/usb adaptor and talk to the micromite plus)
I can no longer see a display. I have tried another spare display and it's not the LCD.
According to the latest micromite plus manual, the LCD uses

OPTION LCDPANEL ILI9341, L, 44, 43, 42
OPTION TOUCH 45, 46
OPTION SDCARD 52

to set it up...
But this give me a blank display.

Issuing
PWM 2,1000,100
will turn on the backlight, and I can vary the brightness by varying the ,100 parameter.
GUI TEST LCDPANEL shows me nothing. At any brightness. No errors, pushing the space bar brings back the command prompt.
I can't calibrate the touch panel because I can't see the points on the screen, but it looks like its waiting for input.

Frustrating, as it used to work, I believe I used the lcd options from the Micromite (not plus) getting started manual previously with the old version of the Micromite.

Any help or suggestions appreciated.

Cheers!

Andy (VK5LA)
Winkie, S.A.

Grogster

Admin Group

Joined: 31/12/2012
Location: New Zealand
Posts: 9754

Posted: 04:05am 17 Jan 2019

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Does the LCD work if you flash an older version of the firmware back into it?
I have not seen this issue myself, but anything is possible.

Do you happen to have a logic analyser?
If you do, you can connect it up to the LCD SPI and control pins, and see if the output shows on the analyser, which would tell you if you have the expected signals.

Generally, these LCD's just work without much pain.

Smoke makes things work. When the smoke gets out, it stops!

erbp
Senior Member

Joined: 03/05/2016
Location: Australia
Posts: 195

Posted: 04:10am 17 Jan 2019

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According to the SC article (Nov 2016), the correct setup for their version of the MM+ Backpack is:

OPTION LCDPANEL, ILI9341, L, 2, 23, 29
OPTION TOUCH 1, 3
OPTION SDCARD 21, 22 or just OPTION SDCARD 21

Cheers,
Phil.

Correction for a typo above:

OPTION LCDPANEL ILI9341, L, 2, 23, 29 (no comma after LCDPANEL)Edited by erbp 2019-01-18

Grogster

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Joined: 31/12/2012
Location: New Zealand
Posts: 9754

Posted: 04:16am 17 Jan 2019

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That's a point.
That's a really good point.
Are you sure you are using the correct pins?

Smoke makes things work. When the smoke gets out, it stops!

vk5la
Newbie

Joined: 05/03/2017
Location: Australia
Posts: 13

Posted: 04:44am 17 Jan 2019

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Thanks for the heads up,
I�ll try those settings.
I�m also guessing it�s some kind of pin mapping issue.
Cheers!

Andy (VK5LA)
Winkie, S.A.

vk5la
Newbie

Joined: 05/03/2017
Location: Australia
Posts: 13

Posted: 08:16am 17 Jan 2019

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Aaaaand that was it.
Using the values from the Silicon Chip Article worked a treat.
Is there any way to set the Micromite backlight on permanently in options or start up?
I have to use the PWM 2,1000,100 command, every time It�s reset.
Even if I download a program like one of Geoff�s examples to it, it won�t display anything until I ad that like to the beginning of the software...ideas?

Cheers

Andy (VK5LA)
Winkie, S.A.

Geoffg

Guru

Joined: 06/06/2011
Location: Australia
Posts: 3308

Posted: 11:54am 17 Jan 2019

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This is a "feature" of the Silicon Chip design.

The culprit is the 10K resistor on pin 53 of the Micromite - it connects to ground so it acts as a pull down when the pin should have been pulled up. To fix this you could mount the resistor vertically (like a tombstone) then run some fine wire from the top of it to a handy source of 3.3V.

Geoff Graham - http://geoffg.net

vk5la
Newbie

Joined: 05/03/2017
Location: Australia
Posts: 13

Posted: 12:01pm 17 Jan 2019

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Thanks Geoffg
I will do just that...
Cheers!

Andy (VK5LA)
Winkie, S.A.

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