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Forum Index : Microcontroller and PC projects : Forget the ILI9488, The ST7796S is the new kid in town

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matherp
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Joined: 11/12/2012
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Posted: 12:24pm 07 May 2025

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Have a look

The moire patterns are artifacts of the camera/screen combination

This panel will be fully supported in V6.00.02RC23. It can work with the existing ILI9488 driver but anything involving reading the VRAM doesn't work.

OPTION LCDPANEL ST7796S,orientation, DCpin, RESETpin, CSpin [,backlightpin] [,INVERT]

It runs in RGB565 both on read and write so updates only take 2/3rds of the time of the ILI9488 and reads are much faster as the data rate doesn't need to be throttled like on the ILI9488 (and the ILI9341)
The screen is 4" and nice and bright and it doesn't need any sort of H/W hack like the ILI9488 to work with touch and the SDcard.

Implementation was reasonably easy except for one gotcha on switching from reading the on-board VRAM to writing it (as used in BLIT and transparent text). To do this I had include a delay until the next HSYNC otherwise the write was simply ignored.

The display supports the new H/W scrolling in portrait mode.
Edited 2025-05-07 22:26 by matherp

ville56
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Joined: 08/06/2022
Location: Austria
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Posted: 12:57pm 07 May 2025

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Peter,
as far as I've seen therer are some variants on Aliexpress available that can be configured in 4 modes:
SPI3, SPI4 wire, parallel 8 bit and 16 bit.

Does it make sense/is it feasable, from your point of view, to also support the parallel modes? This would make a very powerful and flexible display for almost all purposes.

Tnx for your work on MMBasic,
Gerald

73 de OE1HGA, Gerald

stanleyella

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Posted: 03:01pm 07 May 2025

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thanks Peter, checking prices now. using the ILI9488 (and the ILI9341) and diode resistor for reading sd card they are ok
ST7796S not cheap... what is now?
Edited 2025-05-08 01:47 by stanleyella

dddns
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Joined: 20/09/2024
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Posted: 03:38pm 07 May 2025

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matherp said
The display supports the new H/W scrolling in portrait mode.

sounds amazing. Does it reach the ssd1963 in terms of responsiveness and scrolling e.g. in editor?
Edited 2025-05-08 01:38 by dddns

matherp
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Posted: 03:44pm 07 May 2025

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Quote Does it reach the ssd1963 in terms of responsiveness and scrolling e.g. in editor?

Pretty much but only in portrait mode i.e 320x480. All of these smaller displays are organised that way.

Sasquatch

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Joined: 08/05/2020
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Posted: 06:35pm 07 May 2025

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I see that the ST7796 displays are available with either resistive touch or capacitive touch using the FT6336 touch controller for a few $ more.

My experience has been that in general the capacitive touch screens are usually more stable without the calibration offsets and drift that the resistive screens seem to have, although I have no direct experience with the FT6336 screens.

On the other hand, the resistive touch controllers are more "mature" in terms of MMBasic use.

Anyone have any thoughts or experience to share before I order a few panels?
Edited 2025-05-08 04:36 by Sasquatch

-Carl

matherp
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Posted: 06:43pm 07 May 2025

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Resistive touch seems to me to be more accurate. i.e. you can use a fine pointer whereas capacitive you need a finger or finger equivalent which tends to be chunky

stanleyella

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Posted: 08:18pm 07 May 2025

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matherp said Resistive touch seems to me to be more accurate. i.e. you can use a fine pointer whereas capacitive you need a finger or finger equivalent which tends to be chunky

I got the impression capacitive touch better, like phone screens but as said resistive ili works fine, thanks, I think stick with ili.
tbo I like parking monitor with hdmi, vga, composite video £14 if they can make a 8" monitor why not just the screen?

dddns
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Posted: 05:19pm 08 May 2025

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said Does it reach the ssd1963 in terms of responsiveness and scrolling e.g. in editor?

said Pretty much but only in portrait mode i.e 320x480

A bit of a downside with portrait. The ssds seems to get dumped now and the IlI9488 was upgraded..IPS is coming but I think the controller chips will stay

Many thanks for implementing, when I started with PicoMite this was not supported so I bought an ILI9341 but I would like to change it now to st7796 :)
Edited 2025-05-09 03:25 by dddns

matherp
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Posted: 05:32pm 08 May 2025

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SSD is still my favourite and now we have the RP2350B it becomes more practical. The only trouble is that the panels tend to be expensive, looking on buydisplay.com, the cheapest one they have is the 4.3" 480x272 at USD31 with a touch chip

dddns
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Posted: 05:40pm 08 May 2025

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I just saw 7" for 26€, that why I've said

on aliexpress. I'm not allowing cookies but they do tricks. I'm not sure but I've seen them go down now over weeks
Edited 2025-05-09 03:44 by dddns

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