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stanleyella

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Joined: 25/06/2022
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Posted: 07:59pm 27 Oct 2022

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stanleyella

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Posted: 08:07pm 27 Oct 2022

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Sorry . I found an ili9488 that looks pin compatible with ili9341 but does not work.
Looks like problems.manual- OPTION LCDPANEL ILI9488, OR, DC, RESET, CS
Initialises a TFT display using the ILI9488 controller. This supports 480 * 320 resolution. Note that this
controller has an issue with the MISO pin which interferes with the touch controller. For this display to work the
MISO pin must not be connected.
Is this as problematic as the forum thread says?

Mixtel90

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Posted: 08:37pm 27 Oct 2022

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The display controller isn't tri-stating the MISO line so nothing else can use it. Without MISO there's no feedback from the display, so there's no touch (or blit IIRC). Try fitting a 680R resistor between the display MISO and the PicoMite.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

phil99

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Joined: 11/02/2018
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Posted: 08:39pm 27 Oct 2022

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If you don't need Blit, pixel() or Image Save just leave LCD_SDO disconnected.
To restore those functions without affecting touch connect that pin to the Pico MISO pin via a 680 ohm resistor. SD cards may also work, but not guaranteed.

If SD access is unreliable with that fix replace the 680R with a switching transistor controlled by LCD_CS as shown here. A "Double Diode Switch" may also work.

https://www.thebackshed.com/forum/ViewTopic.php?TID=11419&P=3#191429

Further info here.

https://www.thebackshed.com/forum/ViewTopic.php?PID=193293#193293#192349
Edited 2022-10-28 06:43 by phil99

lizby
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Joined: 17/05/2016
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Posted: 08:41pm 27 Oct 2022

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What variety of "does not work"?

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

Tinine
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Posted: 09:07pm 27 Oct 2022

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lizby said What variety of "does not work"?

Mixtel90

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Posted: 09:15pm 27 Oct 2022

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It may be the flash of light and small mushroom cloud that's stopping it.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

stanleyella

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Posted: 10:00pm 27 Oct 2022

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This in teraterm goes nowhere.

> option clear
Error : Invalid Option
> option lcdpanel ili9488, l, gp15, gp14, gp13
Error : Display already configured
option lcdpanel ili9488,l,gp15,gp,14,gp13
Error : Display already configured
> OPTION LIST
OPTION SYSTEM SPI GP18,GP19,GP16
OPTION CPUSPEED (KHz) 252000
OPTION LCDPANEL ILI9341, PORTRAIT,GP15,GP14,GP13
OPTION GUI CONTROLS 10
OPTION TOUCH GP12,GP11
GUI CALIBRATE 1, 197, 3854, 655, -897
OPTION SDCARD GP22

phil99

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Posted: 10:23pm 27 Oct 2022

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TeraTerm isn't the problem. You must be using the wrong manual.

OPTION RESET
will delete everything.

To just change the display try:-

OPTION LCDPANEL Disable

then

OPTION LCDPANEL ILI9488, RLANDSCAPE,GP15,GP14,GP13,GP7

GP7 goes to BL (BACK LIGHT control) or you can tie BL to 3V3.

You will need to redo GUI CALIBRATE

Or try this, it might be close enough.

GUI CALIBRATE 0, 3820, 408, -1306, 946
Edited 2022-10-28 08:31 by phil99

lizby
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Posted: 01:32am 28 Oct 2022

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stanleyella said This in teraterm goes nowhere.

It tells you (twice) what this particular form of "not working" is: "Error : Display already configured"

If you can't find how to re-configure ("OPTION LCDPANEL DISABLE", as said above), you could always try re-flashing the firmware.

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

Mixtel90

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Posted: 06:58am 28 Oct 2022

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... But for goodness sake make sure that you are using the correct manual for the version of the firmware that you are using. It's not just changes because of errors in the manual, there are changes in commands and how they are used too.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

stanleyella

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Joined: 25/06/2022
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Posted: 04:17pm 28 Oct 2022

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Mixtel90 said ... But for goodness sake make sure that you are using the correct manual for the version of the firmware that you are using. It's not just changes because of errors in the manual, there are changes in commands and how they are used too.

I am using NON vga ie lcd version and thanks but not the brightest colour colour in the box. I wish I had not found this display but seems it works. Thanks for advice.

Mixtel90

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Posted: 05:59pm 28 Oct 2022

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It wasn't the VGA/non-VGA thing that I meant, it was the actual version number. The manuals are always behind the beta versions as it is but there's no need to make things any more difficult than you need to. :)

Glad it's working now. :)

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

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