ESP32-VGA

Features

• ESP32 Module
• 6-bit VGA color
• 2 x PS-2 DIN connectors
  • 5V mouse/keyboard
  • 3.3V to 5V level shifters
  • 10K pull-ups on both sides
• 2 x FTDI connectors
• 5V DC Jack
• 3.3V regulator (optional)
• GVS pins for extra ESP32 pins
• 95x95mm form factor
• 6-32 mounting holes

ESP-32 Module

• ESP32 DevKit ESP32-WROOM GPIO Pinout
• On board Blue LED = Arduino Pin 2

Module Features

• Architecture: Xtensa Dual-Core 32-bit LX6
• CPU frequency: up to 240MHz
• Total RAM available: 528KB (part of it reserved for system)
• BootROM: 448KB
• Internal FlashROM: none
• External FlashROM: code and data, via SPI Flash; usual size 4MB
• GPIO: 34 (GPIOs are multiplexed with other functions, including external FlashROM, UART, etc.)
• UART: 3 RX/TX UART (no hardware handshaking), one TX-only UART
• SPI: 4 SPI interfaces (one used for FlashROM)
• I2C: 2 I2C (bitbang implementation available on any pins)
• I2S: 2
• ADC: 12-bit SAR ADC up to 18 channels
• DAC: 2 8-bit DACs
• RMT: 8 channels allowing accurate pulse transmit/receive
• Programming: using BootROM bootloader from UART - due to external FlashROM and always-available BootROM bootloader, the ESP32 is not brickable

Video DAC LTSpice Simulation

• Video DAC Simulation files
• Video is 2:2:2 - R:G:B

Summing Resistor DAC - Rev 1 Board

• 5% resistors are "good enough"
• 1V into 75 Ohm VGA load
• 3.3V drive
• ESP32 has 40 mA drive
  • Uses 10 mA (max)
  • R4 = 1.2 mA to -10 mA
  • R3 = 1.1 mA to -5.3 mA
• Output in 4 steps
  • 0V
  • 0.3V
  • 0.65V
  • 0.96V

R-2R DAC - Rev 2 Board

• 5% resistors are "good enough"
• 1V into 75 Ohm VGA load
• 3.3V drive
• ESP32 has 40 mA drive
  • Uses < 15 mA (max)
  • R4 = +1.6 mA to -14.4 mA
  • R3 = +1.6 mA to -14.2 mA
• Output in 4 steps
  • 0V
  • 0.3V
  • 0.7V
  • 1.0V

Headers

H1 - 3.3V SRC select

• 1-2 = Get 3.3V from ESP32 on-board regulator
• 2-3 = Get 3.3V from on-board regulator (Default)

H2 - 5V SRC Select Jumper

• 2x4 header
• Care must be taken to install the correct jumpers
• USB jumper sends out 5V when a USB cable is connected to the ESP32 module
• USB jumper sends 5V into the ESP32 module when there is no USB cable connected to the ESP32 module

Power from DC Jack

• 1-2 = VUSB - Install - 5V goes to ESP (Do not attach USB cable)
• 3-4 = DCIN - Install - Power comes from DC jack
• 5-6 = FTDI5V_1 - Do not install
• 7-8 = FTDI5V_2 - Do not install

Power from USB on ESP32 module

• 1-2 = VUSB - Install - 5V comes from USB on ESP32 module
• 3-4 = DCIN - Do not install
• 5-6 = FTDI5V_1 - Do not install
• 7-8 = FTDI5V_2 - Do not install

Power from FTDI #1

• 1-2 = VUSB - Install - 5V goes to ESP (Do not attach USB cable)
• 3-4 = DCIN - Power comes from DC jack - Do not power
• 7-8 = FTDI5V_2 - Do not install

Power from FTDI #2

• 1-2 = VUSB - Install - 5V goes to ESP (Do not attach USB cable)
• 3-4 = DCIN - Power comes from DC jack - Do not power
• 5-6 = FTDI5V_1 - Do not install
• 7-8 = FTDI5V_2 - Install

Connectors

P3/P4 = GVS

1. GP13
2. GP14
3. GP16
4. GP17
5. GP35
6. GP23
7. VN
8. VP

J3 - PS/2 Keyboard

• Purple DIN 6 connector

J4 - PS/2 Mouse

• DIN 6 connector

J2 - FTDI #1

• Set FTDI jumper to 3.3V

1. GND
2. RTS (Not used)
3. 5V (Power in if H2 is configured)
4. RX (from card to External FTDI)
5. TX (from External FTDI to card)
6. CTS (Not used)

J6 - FTDI #2

• Set FTDI jumper to 3.3V

1. GND
2. RTS (Not used)
3. 5V (Power in if H2 is configured)
4. RX (from card to External FTDI)
5. TX (from External FTDI to card)
6. CTS (Not used)

FabGL GPIOs assignment summary - fabgl dev board rev2

From here

P3 - VGA

  HSync => 23
  VSync => 15
  R0    => 22
  R1    => 21
  G0    => 19
  G1    => 18
  B0    => 5
  B1    => 4

PS/2 - Keyboard

  DAT   => 32
  CLK   => 33

PS/2 - Mouse

  DAT   => 27
  CLK   => 26

Audio

  AUD   => 25

SDCard - HSPI

• Brought to GVS header pins

  MOSI  => 17
  MISO  => 16
  CLK   => 14
  CS    => 13

UART - UART2

  RX    => 34
  TX    => 2

I2C (not usable with VGA)

  SDA   => 4  (conflicts with VGA B1)
  SCL   => 15 (conflicts with VGA VSync)

SPI Display - VSPI (not usable with VGA)

  CLK   => 18 (conflicts with VGA G1)
  MISO  => 19 (conflicts with VGA G0)
  MOSI  => 23 (conflicts with VGA HSync)
  CS    => 5  (conflicts with VGA B0)
  D/C   => 22 (conflicts with VGA R0)
  RESET => 21 (conflicts with VGA R1)

Software

FabGL

Display Controller (VGA, SSD1306), PS/2 Mouse and Keyboard Controller, Graphics Library, Sound Engine, Game Engine and ANSI/VT Terminal for the ESP32

• FabGL - ESP32 Display Controller and Graphics Library
• FabGL Github repo

MicroPython

• MicroPython Homepage
  • Quick reference for the ESP32
  • General information about the ESP32 port
  • Getting started with MicroPython on the ESP32
• GitHub repo (MicroPython)
  • Examples (MicroPython)
  • Libraries (MicroPython)

ESP-IDF

• ESP-IDF Programming Guide

Operating Systems

• FreeRTOS
• ESP32 DevKit v1
• LuaNode
• ESP32 DEVKITV1 module schematics (also helpful discussion)

Arduino Programming

• Board : "DOIT ESP32 DEVKIT V1"

Schematic

• ESP32 VGA Rev 1 Schematic
• ESP32 VGA Rev 2 Schematic
• ESP32-WROOM-32 Datasheet
• ESP32 Module schematic

Prototype

• ESP32-I2C-HUB
• VGAX49
• PS2X49
  • Purple = Keyboard
  • Green = Mouse
• 95mm to 49mm Adapter card
• 6-32/4-40 Standoffs, screws, nuts
• Cabling

Assembly Sheet

• ESP-32-VGA Rev 2 Assembly Sheet
• ESP-32-VGA Rev 1 Assembly Sheet