display touch ILI9341 pinout

[giorgino]

I'm testing some displays for my application, and due to its touch sensitive this seems to be the best solution, ( https://www.botnroll.com/en/lcds-displa ... river.html ) BUT I've some trouble with the connection:

first I enable SPI in hardware so I have this: SPI : CLK=18/ MISO=19 / MOSI=23
then I connect: SD_SCK=18, SD_DO=19; SD_DI=23


but i'm not sure where to connect other pin, for example the ACTUATOR (
GPIO → TFT CS:GPIO-14
GPIO → TFT DC:GPIO-27
GPIO → TFT RST:
)
in display ther is "SD_SS SD card SPI bus chip select signal, low level enable" and sounds like a DC, but also pins 3 and 4 seems good

do you have any idea?
thanks

(I will need to get the touch input, but this will be a next issue )

[Ath]

Please DO NOT power the board with 5V, use 3.3V, as the ESP works at 3.3V, so the 'high' levels will be too low for the display to recognize, and the ESP might get damaged with the high voltages on its GPIOs!

The most common problem is that you probably didn't connect the backlight (usually marked BL/BLK/LED) either to +3.3V or the designated GPIO pin, so you can set the brightness, configurable in the device configuration. Without backlight it's very hard to see the content of the screen

The RST (reset) pin is not required to be connected, but will be used when configured.
The DC configuration should be on the LCD_RS pin, that's a bit of a strange label they applied.

Looking at the photos they mayhave either got their descriptions wrong, or the photos wrong, as that seems to be an ILI9486 or ILI9488 display, with the 8 bit parallel bus, the ILI9341 uses a 4-wire SPI bus.

For the touch you can connect the CLK, MISO and MOSI in parallel to the connection of the TFT, but have to choose separate GPIOs for CS and DC (DC might not be available, but CS is). Assuming the touch panel is controlled by a XPT2048 you will need a Display or MAX build, as that are the only builds that have plugin P099 included.

[giorgino]

mmmhm... yesterday night many tries with 5v connected! sometimes espeasy went offline, then went back alive....

[giorgino]

sorry, you say:

Looking at the photos they mayhave either got their descriptions wrong, or the photos wrong, as that seems to be an ILI9486 or ILI9488 display, with the 8 bit parallel bus, the ILI9341 uses a 4-wire SPI bus.

In the webpage they say this:

17 SD_SS SD card SPI bus chip select signal, low level enable
18 SD_DI SD card SPI bus MOSI signal
19 SD_DO SD card SPI bus MISO signal
20 SD_SCK SD card SPI bus clock signal

(I don't know much about SPI protocol) isn't it good for the connection?

[TD-er]

SPI is a perfectly fine protocol, as is "parallel".
However they are not the same and thus a device with a "parallel" bus cannot be connected to a SPI controller. (and vice verse)

SPI is a serial protocol, so typically you need fewer pins to transfer the data.
There is a "Master" and 1 or more "Slave" devices.
SPI needs a clock and a data line for each direction.
Since you can connect several SPI devices to the same SPI bus, you also need a "CS" (Chip Select) pin to tell a SPI device you're talking to that device. Sometimes "CS" is also called "SS" as in "Slave Select".
That adds up to 4 pins for SPI.

For some devices you only need to write to the device, and thus you don't need a "MISO" pin (Master In, Slave Out).
Those can be controlled with 3 pin SPI.

As mentioned, you can have multiple devices on the same SPI bus, but you must make sure to use the correct CS pin (or "SS") when trying to communicate with a specific SPI slave device.
"SD_SS" in your list looks like it is the "Slave Select" of an SD card reader slot.

What you need to look for is whether the display controller on that board is also connected to this SPI bus, or that it may have a number of other pins.
If you see multiple data pins (either labelled with a "D" or "Q"), you have a display controller with a parallel bus.
Those cannot be used via the SPI bus.

[giorgino]

so you say that, just to start, it should be enough to connect GND,3.3, LCD_RS (27 - DC), LCD_CS (14,CS) , LCD_RST (26 RST) ?
the display in this condition produce some blinks, random and fast
i can't find a a back light pin so I've connected nothing
Any idea?

[TD-er]

... or post a photo of the pins on the board (including their silkscreen labels) and a photo of the display controller chip.
And maybe also a link to the seller page.

[giorgino]

https://www.botnroll.com/en/lcds-displa ... river.html

[giorgino]

display.jpg (121.93 KiB) Viewed 3562 times

[TD-er]

Hmm that's strange...
On the left side you can see the parallel interface for the display.
See the pins LCD_D0 ... LCD_D7

But on the right LCD_RD, LCD_WR, LCD_CS

SPI pins are called MISO (Master In, Slave Out) and MOSI (Master Out, Slave In).

So I guess the LCD_RD is an output pin and thus MISO.
LCD_WR looks like an input pin -> MOSI.

I think LCD_CS is the chip select

LCD_RST seems like a reset. LCD_RS is a bit unclear to me. Maybe that's the clock?

[Ath]

I don't expect this board to be an ILI9341, but the ILI948x variant with 8 bit parallel interface (sometimes called '8080'). That's currently not supported by ESPEasy, and I'm not sure we will ever, as it requires about 12 pins to connect. That's probably fine on a single-purpose Arduino board, but for most ESP8266 you just don't have enough available GPIOs. On ESP32 boards it's technically possible, but I'm not enthusiastic about it yet.

[giorgino]

ok, so this display is not good for my project. Can you suggest me a device with this caracteristic?

I need tft color 2,4 or 3,5", with touch zone. the touch need to be easy, with big size ("page scrolling", "reset counter","wake") (capacitive instead of resistive?)

the project will live on a sailing boat, very "sensible" to energy umanagement (battery, solar panel, etc), so a low consuption display will be very appreciate

[Ath]

For low consumption displays you will be directed towards ePaper (or eInk), but I'm not sure if they are available with touch screen.

A very nice IPS display (ST7796 supported by P116), with capacitive touch screen that I also have an open PR for, is the WT32-SC01 I bought from Alibaba.com (didn't find the 16MB version cheaper anywhere else, so you shouldn't even consider the 4MB).

Also the 'real' ILI9341 is plenty available from Aliexpress, in several sizes, with or without touch (usually XPT2048, supported via P099).

[giorgino]

OK I have a WT32-sc01-plus, used with a demo workbench (never been able to go over the demo)

so can I burn an espeasy on it? great !

wich release do you suggest?
I've seen it's a ESP32-s3 with a built in display , are you?

and then I will have my gpio for connecting peripherals?
I see ther is only a 485 connector and an " Extended IO Interface"

[giorgino]

mounted the last displat agoust 2023, BUT nothing appear on the display

this from datasheet:

BL_PWM GPIO 45 Backlight control, active high
LCD_RESET GPIO 4 LCD reset, multiplexed with touch reset
LCD_RS GPIO 0 Command/Data selection
LCD_WR GPIO 47 Write clock
LCD_TE GPIO 48 Frame sync
LCD_DB0 GPIO 9
LCD_DB1 GPIO 46
LCD_DB2 GPIO 3
LCD_DB3 GPIO 8
LCD_DB4 GPIO 18
LCD_DB5 GPIO 17
LCD_DB6 GPIO 16
LCD_DB7 GPIO 15
TP_INT GPIO 7 Touch interrupt
TP_SDA GPIO 6 Touch IIC data
TP_SCL GPIO 5 Touch IIC clock
TP_RST GPIO 4 Touch reset, multiplexed with LCD reset

in the device I set this:

Device: Display - ST77xx TFT ? i
Name: wt_32
Enabled: x
Actuator
GPIO → CS (optional): - None -
GPIO → DC: GPIO-0 ⚠
GPIO → RES (optional): GPIO-4
Device Settings
GPIO → Backlight (optional): GPIO-45 ⚠
Backlight percentage: 50 [0-100%]
Display button: - None -
Inversed Logic:
Display Timeout: 0
[0 = off]
TFT display model: ST7796 320 x 480px

[giorgino]

WT32 1.jpeg (69.33 KiB) Viewed 3436 times

[TD-er]

I don't know that specific (S3) variant of that display, but why do you need to wire up this "debug" port?
Why not just use the USB port for flashing/powering the display?

[Ath]

This unit has the same 8 bit parallel interface of the other display you showed, so, it's not supported by ESPEasy (yet...).
That's also why I provided a link to the original WT32-SC01 (without -plus) as I already knew the plus variant isn't going to work ...

[giorgino]

I wanna give me another way, today it's arrived a NEXTION, the NX3224F024_011
I see ther is a 0 +5 and tx and rx on serial0

I start now.....

[Ath]

You'll need a level converter between the ESP and the Nextion, or at least, that's strongly advised, as said before, the high-level of 3.3V isn't really enough to properly trigger a 1 on the 5V input, and the other way around, the high-level of the 5V signal is too high for an ESP to handle for a prolonged time, it will probably damage the ESP.

I have received some more displays, that I'll have to investigate what they really are, as there is no marking on the units, other than the (SPI) signal pins.
Available time is a bit tight for the coming days, so it will take a couple of days before I'll get to testing them.

[giorgino]

do you mean to place the level converter between TX and RX on esp and TX Rx on the nextion?

is it possible to send the neXtion in a sleep mode, or a saving energy mode?

(Nice device!)

[giorgino]

do you mean one of these ?

stepper.jpg (64.12 KiB) Viewed 3310 times

[Ath]

do you mean one of these ?

Yes, that will do fine.