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G6EJD / Wemos-1.4TFT-Shield-Examples

ESP8266 and ESP32 examples for the Wemos/Lolin 1.4" TFT shield
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Wemos TFT 1.4" shield #1

Closed OslafEman closed 5 years ago

OslafEman commented 5 years ago

Hi, I hope you'll can help me. I'm working now with MH ET Live mini and some Wemos D1 mini' shields. I don't know about electronics and currently I'm learning to use these amazing devices. In my project I connected a 1.4" TFT shield in the stacked way and it works well, but when I connect it using the TFT I2C connector shield and the TFT cable (all of them bought in the official store) the screen sets on but don't display anything. I tried with two TFT shields and three connector cables without success. Am I missing something? There is not forum o web site where this information is given and the store doesn't respond me. I'm a follower of your videos and your ESP32-ESP8266-File-Download-Upload-Delete-Stream-and-Directory code was very helpful, besides that I saw your video regarding this shield. Thanks in advance. Oslaf

G6EJD commented 5 years ago

You need to use this: esp32-tft-lcd Set your display pins in the code to match the CS, RTS and DC. I do-not know what you are using at the ESP32 end? A wemos D32 pro with a connector on-board?

OslafEman commented 5 years ago

Thanks David, I'm using a "MH ET Live mini ESP32" with the Wemos D1 mini shields. The TFT display works fine if it is stacked, as you can see here. captura6 I need to use a non-stacked connection, so I use a TFT/I2C connector shield (https://www.aliexpress.com/store/product/TFT-I2C-Connector-Shield-V1-1-0-for-LOLIN-WEMOS-D1-mini-1x-TFT-2x-I2C/1331105_32846977179.html?spm=a2g1y.12024536.productList_2559252.subject_1) In the connector shield I redirected the TFT_CS from pin 0 to pin 4 to match the screen configuration, but even so it doesn't work. The screen gets on but doesn't display anything. As I don't know electronics I would like to avoid complicated wiring, soldering, etc., and keep using the stacking shields. This is the kind of connections I'd like to use. captura5

Oslaf

G6EJD commented 5 years ago

OK, thanks the photos' helped a lot with the understanding of the issue.

define TFT_CS 14

define TFT_RST 33

define TFT_DC 27

Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);

In the code definition it is assumed the SPI Bus is connected to the display, which on the MH-T Live is like this: TFT Shield - MHT-LIVE Pin1 - NC Pin2 to MHT GPIO14 Pin3 to MHT 3.3v Pin4 to MHT GPIO18 Pin5 NC Pin6 to MHT GPIO23 Pin7 to MHT GPIO27 Pin8 to MHT GPIO33 Pin9 to MHT Gnd Pin10 to MHT GPIO32

Pin10 is adjacent to the CH340 and Pin1 is next to the ESP32

We know the display will work when stacked onto an MHT-Live ESP32 but as delivered that shield (TFT plus I2C) has no connection for example between TFT_RST and either D1, D3 or D4, you have to choose, similarly for CD and LED. To help clarify, check it out with a DVM where e.g. RST is going, there are solder pads on the rear to choose with a solder bridge.

G6EJD commented 5 years ago

TFT Connector 1 TFT_LED Backlight control pin, default: NC 2 GND 3 TFT_RST TFT RESET pin, default: RST 4 TFT_DC TFT Register select pin, default: D8 (IO15) 5 MOSI SPI MOSI, D7 (IO13) 6 MISO SPI MISO, D6 (IO12) 7 SCK SPI SCK, D5 (IO14) 8 3V3 9 TFT_CS TFT Select pin, default: D0 (IO16) 10 TS_CS Touch Screen Select pin, default: D3 (IO0)

I2C Connector
1    3V3
2    SCL    D1 (IO5)
3    SDA    D2 (IO4)
4    GND

User IO Connector
1    3V3
2    D4 (IO2)
3    D3 (IO0)
4    GND
G6EJD commented 5 years ago

I've been going through the Lolin/Wemos wiki for the display shield and the code I published for the ESP32 has the correct pin definitions, the only pin not connected is the LED power source which is no connected on the rear of the shield, the TFT_DC is connected to GPIO17 and the TFT_CS connected to GPIO16 but crucially TFT_LED is not connected, I suggest connecting it to say 3.3v as a test while the MHT Live is trying to display something.

OslafEman commented 5 years ago

Hi David, thank you very much. Your help guided me in the way of the solution. Finally I have succeeded connecting the 1.4" TFT shield using the TFT/I2C connector shield and the TFT cable. Fortunately I didn't need to do soldering or wiring, just a little modification in the code. captura1 (Apilada = stacked). For the MH ET Live Mini the Wemos 1.4" shield works according the previous image in both modes just changing the pin numbers. I apologize for my poor English.

Oslaf

G6EJD commented 5 years ago

Good to hear it’s working. It would have been better if Wemos (now Lolin) had used the same pins for this connector so that it all worked seamlessly.