Difference between revisions of "ESP32-VGA"
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<video type="youtube">RuGWCMFNtms</video> | <video type="youtube">RuGWCMFNtms</video> | ||
− | [[File: | + | [[File:P968-cropped-720pxV.jpg]] |
== Features == | == Features == | ||
+ | * See [[ESP32-VGA Rev 1]] for older rev card | ||
* [[ESP32]] Module | * [[ESP32]] Module | ||
+ | ** 18 Analog-to-Digital Converter (ADC) channels | ||
+ | ** 10 Capacitive sensing GPIOs | ||
+ | ** 3 UART interfaces | ||
+ | ** 3 SPI interfaces | ||
+ | ** 2 I2C interfaces | ||
+ | ** 16 PWM output channels | ||
+ | ** 2 Digital-to-Analog Converters (DAC) | ||
+ | ** 2 I2S interfaces | ||
* 6-bit VGA color | * 6-bit VGA color | ||
** 2:2:2 R:G:B | ** 2:2:2 R:G:B | ||
Line 13: | Line 22: | ||
** 5V mouse/keyboard | ** 5V mouse/keyboard | ||
** 3.3V to 5V level shifters | ** 3.3V to 5V level shifters | ||
+ | *** Better than 5V keyboard with series resistors | ||
** 10K pull-ups on both sides | ** 10K pull-ups on both sides | ||
* 2 x FTDI connectors | * 2 x FTDI connectors | ||
Line 37: | Line 47: | ||
[[File:esp32-pinout-chip-ESP-WROOM-32.png]] | [[File:esp32-pinout-chip-ESP-WROOM-32.png]] | ||
− | ==== ESP32 Pin Usage - | + | ==== ESP32 Pin Usage - Revs 2, 3 ==== |
− | |||
− | |||
− | |||
− | |||
[[File:ESP-32_VGA_Pinout_Rev2.PNG]] | [[File:ESP-32_VGA_Pinout_Rev2.PNG]] | ||
Line 68: | Line 74: | ||
* Video is 2:2:2 - R:G:B | * Video is 2:2:2 - R:G:B | ||
− | === Summing Resistor DAC === | + | === Summing Video Resistor DAC === |
− | * | + | * Best values (1%) |
− | * | + | ** 422, 845 |
+ | ** 470, 820 are close/standard values | ||
+ | * 0.7V into 75 Ohm VGA load | ||
* 3.3V drive | * 3.3V drive | ||
* ESP32 has [https://www.esp32.com/viewtopic.php?t=5840 40 mA drive] | * ESP32 has [https://www.esp32.com/viewtopic.php?t=5840 40 mA drive] | ||
− | ** Uses | + | ** Uses 8 mA (max) |
− | + | * Output in 4 equal voltage steps | |
− | |||
− | * Output in 4 steps | ||
− | |||
− | |||
− | |||
− | |||
− | [[File: | + | [[File:VGA_Sim_2R_Voltage.PNG]] |
== Headers == | == Headers == | ||
− | + | * The Rev 2 board changes around headers and connectors from the [[ESP32-VGA Rev 1]] board | |
− | + | === H1 - 5V === | |
− | * | + | * The ESP32-VGA can be powered from either the DC Jack or ESP32 USB power |
− | * | + | * '''Warning: Do not power from 5V Power jack and connect USB cable to the ESP32 module at the same time''' |
+ | ** The ESP32 module has blocking diode to protect the module | ||
+ | *** If the 5V DC jack has a power supply attached with lower voltage it could result in the supplied being shorted between the USB 5V and the DC power jack | ||
+ | *** This is not an issue if the DC power jack is disconnected | ||
+ | * This could be used for an external power switch | ||
− | === H2 - | + | === H2/H3 - GVS === |
− | * | + | * 3x4 header |
+ | * Ground/Voltage/Signal lines | ||
− | + | # GPIO35 | |
+ | # GPIO12 | ||
+ | # VN/I39 | ||
+ | # VP/I36 | ||
− | + | == Connectors == | |
− | |||
− | |||
− | |||
− | === | + | === P1 - PS/2 Mouse === |
− | * | + | * DIN 6 connector |
− | + | * ESP32 pins | |
− | |||
− | * | ||
− | == | + | <pre> |
+ | MSEDAT => GPIO27 | ||
+ | MSECLK => GPIO26 | ||
+ | </pre> | ||
− | + | === P2 - PS/2 Keyboard === | |
− | |||
− | |||
− | |||
− | + | * Purple DIN 6 connector | |
+ | * ESP32 pins | ||
− | + | <pre> | |
− | + | KBDAT => GPIO32 | |
− | + | KBCLK => GPIO33 | |
− | + | </pre> | |
− | |||
− | === | + | === P3 - VGA === |
− | * | + | * ESP32 pins |
− | |||
− | |||
− | |||
− | |||
− | == | + | <pre> |
+ | HSync => GPIO23 | ||
+ | VSync => GPIO15 | ||
+ | R0 => GPIO22 | ||
+ | R1 => GPIO21 | ||
+ | G0 => GPIO19 | ||
+ | G1 => GPIO18 | ||
+ | B0 => GPIO5 | ||
+ | B1 => GPIO4 | ||
+ | </pre> | ||
− | === | + | === P4 - Audio Out - RCA Jack === |
− | * | + | * ESP32 pins |
− | + | <pre> | |
− | + | AUD => GPIO25 | |
− | + | </pre> | |
− | |||
− | |||
− | |||
− | |||
− | |||
− | === | + | === J1 - 5V Power === |
− | * | + | * Center +5V |
− | # | + | === J2 - FTDI #1 === |
− | |||
− | |||
− | |||
− | + | * This interface is in common with the USB-to-Serial interface on the ESP32 module | |
− | + | * Pinout | |
− | * | ||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
# GND | # GND | ||
# RTS (Not used) | # RTS (Not used) | ||
− | # 5V ( | + | # 5V (Not used in Rev 2), Connects to J5 on Rev 3 |
# RX (from card to External FTDI) | # RX (from card to External FTDI) | ||
# TX (from External FTDI to card) | # TX (from External FTDI to card) | ||
# CTS (Not used) | # CTS (Not used) | ||
− | ==== Connect to FTDI card | + | <pre> |
+ | RX => GPIO3 | ||
+ | TX => GPIO1 | ||
+ | </pre> | ||
+ | |||
+ | ==== Connect to FTDI card ==== | ||
* Set FTDI jumper to 3.3V | * Set FTDI jumper to 3.3V | ||
− | |||
[[File:FTDI_rot.jpg]] | [[File:FTDI_rot.jpg]] | ||
− | === | + | === J3 - FTDI #2 === |
+ | |||
+ | * Most recent (2020-02) ANSI terminal uses pin 34 for Rx | ||
+ | * Pinout | ||
# GND | # GND | ||
# RTS (Not used) | # RTS (Not used) | ||
# 5V (Power in if [[ESP32-VGA#H2_-_5V_SRC_Select_Jumper|H2 is configured]]) | # 5V (Power in if [[ESP32-VGA#H2_-_5V_SRC_Select_Jumper|H2 is configured]]) | ||
− | # RX (from | + | # RX (from External FTDI to ESP32 card) |
− | # TX (from External FTDI | + | # TX (from ESP32 card to External FTDI) |
# CTS (Not used) | # CTS (Not used) | ||
− | == | + | <pre> |
+ | RX2 => GPIO34 | ||
+ | TX2 => GPIO2 | ||
+ | </pre> | ||
− | * Set FTDI jumper to 3.3V | + | ==== Connect to FTDI card ==== |
− | + | ||
+ | * Set FTDI jumper to 3.3V (image below shows jumper set to 5V which is wrong) | ||
[[File:FTDI_rot.jpg]] | [[File:FTDI_rot.jpg]] | ||
− | === J3 - | + | === J3 - FTDI #2 === |
− | * | + | * Most recent (as of 2020-02) ANSI terminal uses pin 34 for Rx |
− | * ESP32 | + | * Pinout |
+ | |||
+ | # GND | ||
+ | # RTS (Not used) | ||
+ | # 5V Connects to J5 on Rev 3 | ||
+ | # RX (from External FTDI to ESP32 card) | ||
+ | # TX (from ESP32 card to External FTDI) | ||
+ | # CTS (Not used) | ||
<pre> | <pre> | ||
− | + | RX2 => GPIO34 | |
− | + | TX2 => GPIO2 | |
</pre> | </pre> | ||
− | === J4 - | + | === J4 - SD Card === |
− | * | + | * Brought to GVS header pins (Rev 1) |
− | * | + | * Brought to SD Card (Rev 2) |
<pre> | <pre> | ||
− | + | MOSI => GPIO17 | |
− | CLK => | + | MISO => GPIO16 |
+ | CLK => GPIO14 | ||
+ | CS => GPIO13 | ||
</pre> | </pre> | ||
− | === J5 - | + | === J5 - FTDI Power out (Rev 3+ board) === |
− | * | + | * '''Don't install jumpers if an external FTDI interface is used''' |
+ | * Powers external 3.3 interfaces | ||
+ | ** Useful to power external [[DTE]] or [[DCE]] RS-232 card | ||
+ | * Install shunt/jumper at F1PWR to connect FTDI #1 pin J2-2 to +3.3V | ||
+ | * Install shunt/jumper at F2PWR to connect FTDI #2 pin J3-2 to +3.3V | ||
− | + | [[File:J5_Rev3.PNG]] | |
− | |||
− | |||
− | == | + | == VGA - Resistor Selection == |
− | * | + | * ESP32 has a 3.3V driver which can drive more than 10 mA |
+ | * Ideal case drive current | ||
+ | ** 0.7V (full scale VGA level) into 75 Ohms = 9.33 mA | ||
+ | ** 2/3 of the current or 6.16 mA comes from the lower value resistor (digital most significant bit) | ||
+ | ** 1/3 of the current or 3.08 mA comes from the higher value resistor (digital least significant bit) | ||
+ | * R-2R values | ||
+ | ** Ideal resistor values are 417.9 ohms and 835.7 ohms | ||
+ | ** [http://www.brannonelectronics.com/images/STANDARD%20VALUE.pdf Standard value 1% resistors] | ||
+ | ** 1% standard values are [https://www.mouser.com/ProductDetail/652-CR0805FX-4220ELF 422 (Mouser)], [https://www.mouser.com/ProductDetail/603-RC0805FR-07845RL 845 (Mouser)] Ohms | ||
+ | *** Get closest values | ||
+ | *** 0V, 0.228V, 0.460V, 0.693V | ||
+ | * Voltage steps are: | ||
− | + | [[File:VGA_Sim_2R_Voltage.PNG]] | |
− | |||
− | |||
− | |||
− | + | * Current steps are: | |
− | + | [[File:VGA_Sim_2R_Current.PNG]] | |
− | |||
− | |||
− | |||
− | == | + | == FabGL GPIOs assignment summary - fabgl dev board rev2 == |
− | + | [https://github.com/fdivitto/FabGL/blob/master/fabgl%20GPIOs%20assignment.txt From here] | |
− | |||
<pre> | <pre> | ||
− | + | VGA | |
− | + | HSync => 23 | |
− | + | VSync => 15 | |
− | + | R0 => 21 | |
− | + | R1 => 22 | |
+ | G0 => 18 | ||
+ | G1 => 19 | ||
+ | B0 => 4 | ||
+ | B1 => 5 | ||
+ | |||
+ | Audio | ||
+ | AUD => 25 | ||
− | + | PS/2 - Keyboard | |
+ | DAT => 32 | ||
+ | CLK => 33 | ||
− | + | PS/2 - Mouse | |
− | + | DAT => 27 | |
+ | CLK => 26 | ||
− | == | + | SDCard - HSPI |
+ | MOSI => 17 (12 on TTGO/WROVER) | ||
+ | MISO => 16 (2 on TTGO, 35 WROVER) | ||
+ | CLK => 14 | ||
+ | CS => 13 | ||
− | + | UART - UART1 (USB) | |
+ | RX => 3 | ||
+ | TX => 1 | ||
+ | UART - UART2 | ||
+ | RX => 34 | ||
+ | TX => 2 (not usable on TTGO/WROVER with SDCard active) | ||
+ | </pre> | ||
=== I2C (not usable with VGA) === | === I2C (not usable with VGA) === | ||
<pre> | <pre> | ||
− | SDA => | + | SDA => GPIO4 (conflicts with VGA B1) |
− | SCL => | + | SCL => GPIO15 (conflicts with VGA VSync) |
</pre> | </pre> | ||
Line 282: | Line 316: | ||
<pre> | <pre> | ||
− | CLK => | + | CLK => GPIO18 (conflicts with VGA G1) |
− | MISO => | + | MISO => GPIO19 (conflicts with VGA G0) |
− | MOSI => | + | MOSI => GPIO23 (conflicts with VGA HSync) |
− | CS => | + | CS => GPIO5 (conflicts with VGA B0) |
− | D/C => | + | D/C => GPIO22 (conflicts with VGA R0) |
− | RESET => | + | RESET => GPIO21 (conflicts with VGA R1) |
</pre> | </pre> | ||
== Software == | == Software == | ||
− | |||
− | |||
− | |||
− | |||
− | |||
=== FabGL === | === FabGL === | ||
Line 312: | Line 341: | ||
* [http://www.fabglib.org FabGL] - ESP32 Display Controller and Graphics Library | * [http://www.fabglib.org FabGL] - ESP32 Display Controller and Graphics Library | ||
* [https://github.com/fdivitto/fabgl FabGL Github repo] | * [https://github.com/fdivitto/fabgl FabGL Github repo] | ||
+ | * [https://hackaday.com/2020/08/20/esp32-altair-emulator-gets-split-personality/ ESP32 ALTAIR EMULATOR GETS SPLIT PERSONALITY] - Hackaday page | ||
+ | ** [https://github.com/wd5gnr/FabGL FabGL derived build] | ||
==== FabGL Arduino library ==== | ==== FabGL Arduino library ==== | ||
Line 320: | Line 351: | ||
==== Using Latest FabGL builds ==== | ==== Using Latest FabGL builds ==== | ||
+ | |||
+ | * Fabrizio does a nice job of keeping his Arduino libraries up to date but if you want a bleeding edge experience, you can download [https://github.com/fdivitto/fabgl his code from GitHub]. Note, he's in active development so things often change. | ||
Here's how I did it | Here's how I did it | ||
Line 329: | Line 362: | ||
# Compile/download/test the new files. You know it works if you now get sound from Space Invaders. | # Compile/download/test the new files. You know it works if you now get sound from Space Invaders. | ||
# Save as where you would normally save your Arduino sketches. | # Save as where you would normally save your Arduino sketches. | ||
+ | |||
+ | === Arduino Programming === | ||
+ | |||
+ | * [https://randomnerdtutorials.com/installing-the-esp32-board-in-arduino-ide-windows-instructions/ Installing the ESP32 Board in Arduino IDE (Windows, Mac OS X, Linux)] | ||
+ | * Board : "DOIT ESP32 DEVKIT V1" | ||
+ | ** Used Board : ESP32 Dev Module with Tools > Partition Scheme > Huge APP option to run VIC-20 (2022-09) | ||
+ | * DOIT module does not have PSRAM | ||
+ | ** Can't run PC Emulator without PSRAM | ||
+ | * If you try to upload a new sketch to your ESP32 and you get this error message “A fatal error occurred: Failed to connect to ESP32: Timed out… Connecting…“. It means that your ESP32 is not in flashing/uploading mode. | ||
+ | * Press the “Upload” button in the Arduino IDE to upload your sketch | ||
+ | * After you see the “Connecting….” message in your Arduino IDE, release the finger from the “BOOT” button: | ||
+ | |||
+ | [[File:Ardino_ESP32.png]] | ||
=== MicroPython === | === MicroPython === | ||
Line 355: | Line 401: | ||
* [http://land-boards.com/ESP32-VGA/ESP-32_VGA_Rev1_Schematic.pdf ESP32 VGA Rev 1 Schematic] | * [http://land-boards.com/ESP32-VGA/ESP-32_VGA_Rev1_Schematic.pdf ESP32 VGA Rev 1 Schematic] | ||
* [http://land-boards.com/ESP32-VGA/ESP32-VGA_Rev2_Schematic.pdf ESP32 VGA Rev 2 Schematic] | * [http://land-boards.com/ESP32-VGA/ESP32-VGA_Rev2_Schematic.pdf ESP32 VGA Rev 2 Schematic] | ||
+ | * [http://land-boards.com/ESP32-VGA/ESP32-VGA_Rev3_Schematic.pdf ESP32 VGA Rev 3 Schematic] | ||
* [https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32_datasheet_en.pdf ESP32-WROOM-32 Datasheet] | * [https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32_datasheet_en.pdf ESP32-WROOM-32 Datasheet] | ||
* [https://github.com/land-boards/lb-boards/blob/master/ESP32/ESP32-Hub/Parts_/SchematicsforESP32.pdf ESP32 Module schematic] | * [https://github.com/land-boards/lb-boards/blob/master/ESP32/ESP32-Hub/Parts_/SchematicsforESP32.pdf ESP32 Module schematic] | ||
+ | |||
+ | == Rev 3 Changes == | ||
+ | |||
+ | [[File:ESP32-VGA_CAD_REV3.PNG]] | ||
+ | |||
+ | * Adds J5 header to provide power out on FTDI connectors J2, J3 | ||
== Rev 2 Changes == | == Rev 2 Changes == | ||
Line 362: | Line 415: | ||
[[File:ESP32-VGA_CAD_REV2-bw.PNG]] | [[File:ESP32-VGA_CAD_REV2-bw.PNG]] | ||
− | * Swap FTDI pins 4 and 5 ( | + | * '''Rev 1 board won't program or boot with FDTI #2 card attached''' |
+ | ** Earlier FabGL had GPIO12 instead of GPIO34 | ||
+ | ** Move FTDI Rx line (GPIO12 to GPIO34) | ||
+ | * Swap FTDI pins 4 and 5 (FTDI connectors) | ||
** Allow direct connect to FTDI card (no swap) | ** Allow direct connect to FTDI card (no swap) | ||
* Add SD Card connector | * Add SD Card connector | ||
Line 370: | Line 426: | ||
** CS => GPIO 13 | ** CS => GPIO 13 | ||
** Remove I/O pins from GVS connector | ** Remove I/O pins from GVS connector | ||
− | + | * Replace H1/H2 with 1x2 to select/remove DC jack power\ | |
− | + | * Remove Polysilicone fuse | |
− | ** | + | * Change ESP32 board name silkscreen |
− | + | * Add SD card connector | |
− | * | ||
== Prototype == | == Prototype == | ||
Line 391: | Line 446: | ||
== Assembly Sheet == | == Assembly Sheet == | ||
− | * [[ESP32-VGA Rev 2 Assembly Sheet]] | + | * [[ESP32-VGA Rev 3 Assembly Sheet]] (Tindie board) |
+ | * [[ESP32-VGA Rev 2 Assembly Sheet]] (older Tindie board) | ||
* [[ESP-32-VGA Rev 1 Assembly Sheet]] | * [[ESP-32-VGA Rev 1 Assembly Sheet]] |
Revision as of 17:36, 3 September 2022
Contents
Features
- See ESP32-VGA Rev 1 for older rev card
- ESP32 Module
- 18 Analog-to-Digital Converter (ADC) channels
- 10 Capacitive sensing GPIOs
- 3 UART interfaces
- 3 SPI interfaces
- 2 I2C interfaces
- 16 PWM output channels
- 2 Digital-to-Analog Converters (DAC)
- 2 I2S interfaces
- 6-bit VGA color
- 2:2:2 R:G:B
- 2 x PS-2 DIN connectors
- 5V mouse/keyboard
- 3.3V to 5V level shifters
- Better than 5V keyboard with series resistors
- 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
- Uses the ESP32 DevKit ESP32-WROOM GPIO Pinout
- On board Blue LED = Arduino Pin 2
- There are various modules out there with different pinouts, but this card uses this one
ESP-32 Module Pinout
"Chip" on the module
ESP32 Pin Usage - Revs 2, 3
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 Video Resistor DAC
- Best values (1%)
- 422, 845
- 470, 820 are close/standard values
- 0.7V into 75 Ohm VGA load
- 3.3V drive
- ESP32 has 40 mA drive
- Uses 8 mA (max)
- Output in 4 equal voltage steps
Headers
- The Rev 2 board changes around headers and connectors from the ESP32-VGA Rev 1 board
H1 - 5V
- The ESP32-VGA can be powered from either the DC Jack or ESP32 USB power
- Warning: Do not power from 5V Power jack and connect USB cable to the ESP32 module at the same time
- The ESP32 module has blocking diode to protect the module
- If the 5V DC jack has a power supply attached with lower voltage it could result in the supplied being shorted between the USB 5V and the DC power jack
- This is not an issue if the DC power jack is disconnected
- The ESP32 module has blocking diode to protect the module
- This could be used for an external power switch
H2/H3 - GVS
- 3x4 header
- Ground/Voltage/Signal lines
- GPIO35
- GPIO12
- VN/I39
- VP/I36
Connectors
P1 - PS/2 Mouse
- DIN 6 connector
- ESP32 pins
MSEDAT => GPIO27 MSECLK => GPIO26
P2 - PS/2 Keyboard
- Purple DIN 6 connector
- ESP32 pins
KBDAT => GPIO32 KBCLK => GPIO33
P3 - VGA
- ESP32 pins
HSync => GPIO23 VSync => GPIO15 R0 => GPIO22 R1 => GPIO21 G0 => GPIO19 G1 => GPIO18 B0 => GPIO5 B1 => GPIO4
P4 - Audio Out - RCA Jack
- ESP32 pins
AUD => GPIO25
J1 - 5V Power
- Center +5V
J2 - FTDI #1
- This interface is in common with the USB-to-Serial interface on the ESP32 module
- Pinout
- GND
- RTS (Not used)
- 5V (Not used in Rev 2), Connects to J5 on Rev 3
- RX (from card to External FTDI)
- TX (from External FTDI to card)
- CTS (Not used)
RX => GPIO3 TX => GPIO1
Connect to FTDI card
- Set FTDI jumper to 3.3V
J3 - FTDI #2
- Most recent (2020-02) ANSI terminal uses pin 34 for Rx
- Pinout
- GND
- RTS (Not used)
- 5V (Power in if H2 is configured)
- RX (from External FTDI to ESP32 card)
- TX (from ESP32 card to External FTDI)
- CTS (Not used)
RX2 => GPIO34 TX2 => GPIO2
Connect to FTDI card
- Set FTDI jumper to 3.3V (image below shows jumper set to 5V which is wrong)
J3 - FTDI #2
- Most recent (as of 2020-02) ANSI terminal uses pin 34 for Rx
- Pinout
- GND
- RTS (Not used)
- 5V Connects to J5 on Rev 3
- RX (from External FTDI to ESP32 card)
- TX (from ESP32 card to External FTDI)
- CTS (Not used)
RX2 => GPIO34 TX2 => GPIO2
J4 - SD Card
- Brought to GVS header pins (Rev 1)
- Brought to SD Card (Rev 2)
MOSI => GPIO17 MISO => GPIO16 CLK => GPIO14 CS => GPIO13
J5 - FTDI Power out (Rev 3+ board)
- Don't install jumpers if an external FTDI interface is used
- Powers external 3.3 interfaces
- Install shunt/jumper at F1PWR to connect FTDI #1 pin J2-2 to +3.3V
- Install shunt/jumper at F2PWR to connect FTDI #2 pin J3-2 to +3.3V
VGA - Resistor Selection
- ESP32 has a 3.3V driver which can drive more than 10 mA
- Ideal case drive current
- 0.7V (full scale VGA level) into 75 Ohms = 9.33 mA
- 2/3 of the current or 6.16 mA comes from the lower value resistor (digital most significant bit)
- 1/3 of the current or 3.08 mA comes from the higher value resistor (digital least significant bit)
- R-2R values
- Ideal resistor values are 417.9 ohms and 835.7 ohms
- Standard value 1% resistors
- 1% standard values are 422 (Mouser), 845 (Mouser) Ohms
- Get closest values
- 0V, 0.228V, 0.460V, 0.693V
- Voltage steps are:
- Current steps are:
FabGL GPIOs assignment summary - fabgl dev board rev2
VGA HSync => 23 VSync => 15 R0 => 21 R1 => 22 G0 => 18 G1 => 19 B0 => 4 B1 => 5 Audio AUD => 25 PS/2 - Keyboard DAT => 32 CLK => 33 PS/2 - Mouse DAT => 27 CLK => 26 SDCard - HSPI MOSI => 17 (12 on TTGO/WROVER) MISO => 16 (2 on TTGO, 35 WROVER) CLK => 14 CS => 13 UART - UART1 (USB) RX => 3 TX => 1 UART - UART2 RX => 34 TX => 2 (not usable on TTGO/WROVER with SDCard active)
I2C (not usable with VGA)
SDA => GPIO4 (conflicts with VGA B1) SCL => GPIO15 (conflicts with VGA VSync)
SPI Display - VSPI (not usable with VGA)
CLK => GPIO18 (conflicts with VGA G1) MISO => GPIO19 (conflicts with VGA G0) MOSI => GPIO23 (conflicts with VGA HSync) CS => GPIO5 (conflicts with VGA B0) D/C => GPIO22 (conflicts with VGA R0) RESET => GPIO21 (conflicts with VGA R1)
Software
FabGL
- Display Controller features/applications
- VGA
- SSD1306
- PS/2 Mouse and Keyboard Controller
- Graphics Library
- Sound Engine
- Game Engine
- ANSI/VT Terminal for the ESP32
FabGL Libraries
- FabGL - ESP32 Display Controller and Graphics Library
- FabGL Github repo
- ESP32 ALTAIR EMULATOR GETS SPLIT PERSONALITY - Hackaday page
FabGL Arduino library
Installing the released library
Using Latest FabGL builds
- Fabrizio does a nice job of keeping his Arduino libraries up to date but if you want a bleeding edge experience, you can download his code from GitHub. Note, he's in active development so things often change.
Here's how I did it
- Install drivers via Arduino from the Library Manager. These are not the latest files. Space Invaders should run but not have sound (as of now because it's the older version).
- Move the FabGL from the Arduino libraries file folder to the desktop.
- Copy the FabGL from the GitHub download to the Arduino files folder (where you removed the other folder).
- Examples will now be the latest.
- Compile/download/test the new files. You know it works if you now get sound from Space Invaders.
- Save as where you would normally save your Arduino sketches.
Arduino Programming
- Installing the ESP32 Board in Arduino IDE (Windows, Mac OS X, Linux)
- Board : "DOIT ESP32 DEVKIT V1"
- Used Board : ESP32 Dev Module with Tools > Partition Scheme > Huge APP option to run VIC-20 (2022-09)
- DOIT module does not have PSRAM
- Can't run PC Emulator without PSRAM
- If you try to upload a new sketch to your ESP32 and you get this error message “A fatal error occurred: Failed to connect to ESP32: Timed out… Connecting…“. It means that your ESP32 is not in flashing/uploading mode.
- Press the “Upload” button in the Arduino IDE to upload your sketch
- After you see the “Connecting….” message in your Arduino IDE, release the finger from the “BOOT” button:
MicroPython
- MicroPython Homepage
- GitHub repo (MicroPython)
ESP-IDF
Operating Systems
- FreeRTOS
- ESP32 DevKit v1
- LuaNode
- ESP32 DEVKITV1 module schematics (also helpful discussion)
Schematic
- ESP32 VGA Rev 1 Schematic
- ESP32 VGA Rev 2 Schematic
- ESP32 VGA Rev 3 Schematic
- ESP32-WROOM-32 Datasheet
- ESP32 Module schematic
Rev 3 Changes
- Adds J5 header to provide power out on FTDI connectors J2, J3
Rev 2 Changes
- Rev 1 board won't program or boot with FDTI #2 card attached
- Earlier FabGL had GPIO12 instead of GPIO34
- Move FTDI Rx line (GPIO12 to GPIO34)
- Swap FTDI pins 4 and 5 (FTDI connectors)
- Allow direct connect to FTDI card (no swap)
- Add SD Card connector
- MISO => GPIO 16
- MOSI => GPIO 17
- CLK => GPIO 14
- CS => GPIO 13
- Remove I/O pins from GVS connector
- Replace H1/H2 with 1x2 to select/remove DC jack power\
- Remove Polysilicone fuse
- Change ESP32 board name silkscreen
- Add SD card connector
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
- ESP32-VGA Rev 3 Assembly Sheet (Tindie board)
- ESP32-VGA Rev 2 Assembly Sheet (older Tindie board)
- ESP-32-VGA Rev 1 Assembly Sheet