• ESP32 based + SDReader + 2.8' TFT (320x240) with Resistive touch screen
• Aliexpress

Features

• ESP32
• FLASH: 4MB (Up to 16MB with hardware mod)
• PSRAM: NO (Up to 8MB with hardware mod - See Hardware Mod section below...)
• Micro-SD card slot (SPI)
• 2.8-inch 320x240 TFT display - ILI9341 (SPI)
• Resistive touch panel - XPT2046 (SPI)
• 1 RGB led
• 1 USB-Micro to Serial 0 (CH340C)
• Boot and reset buttons
• Power Supply: 5V / 1A
• Header P3 : GND - GPIO 35 - GPIO 22 - GPIO 21
• Header CN1 : GND - NC (or GPIO 22 on some boards) - GPIO 27 - V3.3
• Header power : VIN - TX - RX - GND

Pins

ESP Pin	GPIO	Description
1	GND	Ground
2	VCC	+3V3
3	EN	RST / TFT_RST (Reset / LCD)
4	GPIO36	SENSOR_VP / TP_IRQ (Touchscreen)
5	GPIO39	SENSOR_VN / TP_OUT (Touchscreen)
6	GPIO34	ADC
7	GPIO35	Header P3 Pin 3
8	GPIO32	TP_DIN (Touchscreen)
9	GPIO33	TP_CS (Touchscreen)
10	GPIO25	TP_CLK (Touchscreen)
11	GPIO26	AUDIO IN-
12	GPIO27	Header CN1 Pin 2
13	GPIO14	TFT_SCK (TFT)
14	GPIO12	TFT_SDO (TFT)
15	GND	Ground
16	GPIO13	TFT_SDI (TFT)
17	SHD/SD2	HOLD (SPI Flash / PSRAM*)
18	SWP/SD3	WP (SPI Flash / PSRAM*)
19	SCS/CMD	CS (SPI Flash)
20	SCK/CLK	SCK (SPI Flash)
21	SDO/SD0	SO (SPI Flash / PSRAM*)
22	SDI/SD1	SI (SPI Flash / PSRAM*)
23	GPIO15	TFT_CS (TFT)
24	GPIO02	TFT_RS (TFT)
25	GPIO0	BOOT_SW
26	GPIO04	LED_RGB
27	GPIO16	LED_RGB (PSRAM_CS*)
28	GPIO17	LED_RGB (PSRAM_SCK*)
29	GPIO05	TF_CS (SD Card)
30	GPIO18	TF_CLK (SD Card)
31	GPIO19	MCU_MISO (SD Card)
32	NC	NA
33	GPIO21	TFT_BL (TFT) / Header P3 Pin 1
34	RXD0	RXD2 Header P1 Pin 3
35	TXD0	TXD2 Header P1 Pin 2
36	GPIO22	Header P3 Pin 2 (also Header CN1 Pin 3 on some boards)
37	GPIO23	MCU_MOSI (SD Card)
38	GND	Ground
39	GND	Ground

* Requires Hardware Mod

Hardware Mod (Add External PSRAM)

This board has an external SOIC-8 footprint near the ESP32 module that is wired in parallel to the built-in SPI Flash. This can be used (with some modifications) to add an external SPI PSRAM in order to achieve more available memory.

NOTE: There are (at least) two revisions of this board.

• On one revision, the external SOIC-8 footprint is populated with the SPI Flash IC. See Option 1 below for Mod details.
• On another revision, the external SOIC-8 footprint is un-populated (the SPI flash is built into the ESP32 module). See Option 2 below for Mod details.

In either case, one will first need to acquire a compatible PSRAM IC. This can be desoldered from an existing board (i.e. ESP32-CAM board), or purchased separately. Make sure whatever IC you choose supports 3.3v and at least 80 MHz. Ideally it should support Quad SPI (QIO) as well.

Some compatible 8MB PSRAM ICs are:

• ESP-PSRAM64H
• IPS6404L-SQ-SPN
• APM6404-SQ-SPN
• APS6404L-3SQR-SN

NOTE: Remember to choose the correct variant in CMakeLists.txt to enable PSRAM support.

Option 1

On this revision, the PSRAM must be piggy-backed on top of the external Flash IC.

• Place the PSRAM IC directly on top of the Flash IC (with the same orientation for Pin 1).
• Connect all Pins (except for Pins 1 & 6) directly to the cooresponding pins on the Flash IC below.
• Remove the RGB LED, as it conflicts with GPIO 16 & 17 that are needed for the new PSRAM IC.
• Connect a bodge wire from Pin 1 to GPIO 16 (can use the Pad of the RGB LED closest to the ESP32 module).
• Connect a bodge wire from Pin 6 to GPIO 17 (can use the Pad of the RGB LED farthest from the ESP32 module on the bottom row).
• Attach a 10k resistor between Pins 1 & 8 of the PSRAM IC. This is a pull-up resistor that ensures the PSRAM is deselected by default (i.e. when the Flash IC is in use).

Option 2

On this revision, the PSRAM can be soldered to the un-populated SOIC-8 footprint.

• Cut the PCB trace going to Pin 1 as well as the PCB trace going to pin 6.
• Solder the PSRAM IC to the SOIC-8 footprint (making sure Pin 1 is in the correct orientation).
• Remove the RGB LED, as it conflicts with GPIO 16 & 17 that are needed for the new PSRAM IC.
• Connect a bodge wire from Pin 1 to GPIO 16 (can use the Pad of the RGB LED closest to the ESP32 module).
• Connect a bodge wire from Pin 6 to GPIO 17 (can use the Pad of the RGB LED farthest from the ESP32 module on the bottom row).
• Attach a 10k resistor between Pins 1 & 8 of the PSRAM IC. This is a pull-up resistor that ensures the PSRAM is deselected by default (i.e. when the Flash IC is in use).

Before:

After:

Because I do not have the 2 others boards, I cannot do an update here, if you are able to, please contact me I will be happy to update the documentation.

I enclose also the files here for reference: