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README.md

ESP32 Multi IO

The Duodyne ESP32 board provides the following functions for your Duodyne computer

  • ANSI Console
  • Graphics
  • Sprites
  • Sound
  • Dual USB Serial Support
  • WiFi
  • Keyboard
  • Mouse

This board relies heavily on the FabGL library from Fabrizio Di Vittorio. More information can be found HERE

ESP32 BOM

Qty Reference(s) Value Notes
14 C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C17, C18 0.1uf
3 C13, C14, C16 10uf
1 C15 100nF
1 D1 LED
4 D2, D3, D4, D5 1N4001
1 J1 2x5 pin header, right angle KEYBOARD AND MOUSE
1 J2 1x2 pin header, right angle AUDIO OUT
1 J3 1x3 pin header, right angle ESP_SERIAL_1
1 J4 1x3 pin header, right angle ESP_SERIAL_0
1 J5 HD15 Female PCB VGA Connector VGA
1 J6 1x3 pin header RESET SEL
1 J7 2x6 pin header, right angle IO PORT ADDR
1 J8 Mini Din, 6 pos female PS/2 Keyboard
1 J9 Mini Din, 6 pos female PS/2 Mouse
1 J10 2x7 pin header, right angle VGA
3 P1, P2, P3 02X25 pin header, right angle
1 P4 1x4 pin header BYPASS
1 R1 470ohm
1 R2 270ohm
4 R3, R4, R10, R11 120ohm
1 R5 150ohm
2 R6, R8 2Kohm
2 R7, R9 1Kohm
3 R12, R14, R16 400ohm Used for VGA voltage divider, precise value not required
3 R13, R15, R17 800ohm Used for VGA voltage divider, precise value not required
2 R18, R19 0ohm
1 RN1 1Kohm, networked, 9 pin, 8 resistor
1 RN2 10Kohm, networked, 9 pin, 8 resistor
1 U1 74LS04
3 U2, U4, U5 74LS32
2 U3, U17 74LS07
2 U6, U8 74HC595
2 U7, U9 74HC165
3 U10, U13, U15 74LS244
2 U11, U12 ESP-WROOM-32 Dev Module Such As: https://www.amazon.com/ESP-WROOM-32-Development-Microcontroller-Integrated-Compatible/dp/B08D5ZD528
1 U14 74LS245
1 U16 74LS688

ESP32 Firmware Installation

The firmware for this board requires that platformio be installed on your system.

To install platformio core for your operating system see the directions HERE.
Make sure you follow the additional directions to install the shell commands.

On linux systems it may be necessary to update permissions for the device that is autocreated for the ESP32. More details
Once platformio is properly setup on your system, you should be able to build and deploy the firmware to the ESP32.

To build and install the ESP firmware:

Take the ESP32 device you have designated as ESP0 and with it NOT INSTALLED in the Duodyne card, plug it into your computer via USB. change directory to the ESP0Firmware folder on your PC and from the operating system prompt type

pio run -t upload

Over the next couple of minutes you should see the build and upload process something like this:

dwerner@lserver02:/lserver03/fileserv/Development/Vintage/Projects/Duodyne/Z80ESP/ESP0Firmware$ pio run -t upload
Processing esp32dev (platform: espressif32; board: esp32dev; framework: arduino)
-----------------------------------------------------------------------------------------------------------------------
Verbose mode can be enabled via `-v, --verbose` option
CONFIGURATION: https://docs.platformio.org/page/boards/espressif32/esp32dev.html
PLATFORM: Espressif 32 (6.3.2) > Espressif ESP32 Dev Module
HARDWARE: ESP32 240MHz, 320KB RAM, 4MB Flash
DEBUG: Current (cmsis-dap) External (cmsis-dap, esp-bridge, esp-prog, iot-bus-jtag, jlink, minimodule, olimex-arm-usb-ocd, olimex-arm-usb-ocd-h, olimex-arm-usb-tiny-h, olimex-jtag-tiny, tumpa)
PACKAGES:
 - framework-arduinoespressif32 @ 3.20009.0 (2.0.9)
 - tool-esptoolpy @ 1.40501.0 (4.5.1)
 - tool-mkfatfs @ 2.0.1
 - tool-mklittlefs @ 1.203.210628 (2.3)
 - tool-mkspiffs @ 2.230.0 (2.30)
 - toolchain-xtensa-esp32 @ 8.4.0+2021r2-patch5
LDF: Library Dependency Finder -> https://bit.ly/configure-pio-ldf
LDF Modes: Finder ~ deep+, Compatibility ~ soft
Found 34 compatible libraries
Scanning dependencies...
Dependency Graph
|-- FabGL @ 1.0.9
|-- SPI @ 2.0.0
|-- Preferences @ 2.0.0
Building in release mode
Retrieving maximum program size .pio/build/esp32dev/firmware.elf
Checking size .pio/build/esp32dev/firmware.elf
Advanced Memory Usage is available via "PlatformIO Home > Project Inspect"
RAM:   [=         ]   9.3% (used 30632 bytes from 327680 bytes)
Flash: [=====     ]  46.4% (used 608561 bytes from 1310720 bytes)
Configuring upload protocol...
AVAILABLE: cmsis-dap, esp-bridge, esp-prog, espota, esptool, iot-bus-jtag, jlink, minimodule, olimex-arm-usb-ocd, olimex-arm-usb-ocd-h, olimex-arm-usb-tiny-h, olimex-jtag-tiny, tumpa
CURRENT: upload_protocol = esptool
Looking for upload port...
Auto-detected: /dev/ttyUSB0
Uploading .pio/build/esp32dev/firmware.bin
esptool.py v4.5.1
Serial port /dev/ttyUSB0
Connecting.....
Chip is ESP32-D0WD-V3 (revision v3.0)
Features: WiFi, BT, Dual Core, 240MHz, VRef calibration in efuse, Coding Scheme None
Crystal is 40MHz
MAC: 08:b6:1f:33:39:fc
Uploading stub...
Running stub...
Stub running...
Changing baud rate to 460800
Changed.
Configuring flash size...
Flash will be erased from 0x00001000 to 0x00005fff...
Flash will be erased from 0x00008000 to 0x00008fff...
Flash will be erased from 0x0000e000 to 0x0000ffff...
Flash will be erased from 0x00010000 to 0x000a4fff...
Compressed 17488 bytes to 12168...
Writing at 0x00001000... (100 %)
Wrote 17488 bytes (12168 compressed) at 0x00001000 in 0.5 seconds (effective 287.3 kbit/s)...
Hash of data verified.
Compressed 3072 bytes to 146...
Writing at 0x00008000... (100 %)
Wrote 3072 bytes (146 compressed) at 0x00008000 in 0.0 seconds (effective 571.2 kbit/s)...
Hash of data verified.
Compressed 8192 bytes to 47...
Writing at 0x0000e000... (100 %)
Wrote 8192 bytes (47 compressed) at 0x0000e000 in 0.1 seconds (effective 829.3 kbit/s)...
Hash of data verified.
Compressed 608928 bytes to 309667...
Writing at 0x00010000... (5 %)
Writing at 0x00020854... (10 %)
Writing at 0x0002f631... (15 %)
Writing at 0x0003b66a... (21 %)
Writing at 0x0004b725... (26 %)
Writing at 0x00050794... (31 %)
Writing at 0x00056585... (36 %)
Writing at 0x0005c2fd... (42 %)
Writing at 0x0006271e... (47 %)
Writing at 0x000684b2... (52 %)
Writing at 0x0006dceb... (57 %)
Writing at 0x00073098... (63 %)
Writing at 0x0007864e... (68 %)
Writing at 0x0007de33... (73 %)
Writing at 0x0008412b... (78 %)
Writing at 0x0008c053... (84 %)
Writing at 0x00094cba... (89 %)
Writing at 0x0009a559... (94 %)
Writing at 0x0009f9b7... (100 %)
Wrote 608928 bytes (309667 compressed) at 0x00010000 in 8.0 seconds (effective 606.6 kbit/s)...
Hash of data verified.

Leaving...
Hard resetting via RTS pin...
============================================ [SUCCESS] Took 22.49 seconds ============================================

Once this is done you can install ESP0 into U12 on your Duodyne board. Then repeat the process for the ESP1 and install into U13.

ESP32 Communication Protocol

The ESP32 board communicates with your system via 3 ports, two IO ports and one status port.

The default configuration sets the base IO to $9C. IO Communication with ESP0 is at base port, ESP1 is at base port +1 and the status register is at base port +2.

ESPBASE         EQU $9C         ; Base Port
ESP0:           EQU ESPBASE     ; ESP0 IO PORT

ESP1:           EQU ESPBASE+1   ; ESP1 IO PORT

ESP_STATUS:     EQU ESPBASE+2   ; ESP  STATUS PORT
                                ; MSB XX XX S S S S S
                                ;           | | | | |- ESP0 READY_OUTPUT
                                ;           | | | |--- ESP0 BUSY
                                ;           | | |----- ESP0 SPARE (unused)
                                ;           | |------- ESP1 READY_OUTPUT
                                ;           |--------- ESP1 BUSY

The communication process is fairly straight forward. Upon reset, the ESP will initialize, set BUSY and READY_OUTPUT to low and wait for an opcode.

To send an opcode or data to the ESP:

  • wait for ESPx BUSY bit to go low (a timeout is suggested)
  • write the opcode or data to the ESPx IO port
  • it is a best practice to wait for ESPx BUSY bit to go high then low (a timeout is suggested) before sending the next byte

If an "out of sync" occurrs, where the ESP is waiting for data rather than an opcode and the host driver is unsure of the state of the ESP, it is possible to resync the ESP back to the "waiting for opcode" state by sending a stream of NULL bytes to the IO port. A stream of more than 25 NULLS should always safely return the ESP back to the "waiting for opcode" state.

Some Opcodes will return one or more bytes to the host system. For those opcodes

  • wait for ESPx BUSY bit to go low (a timeout is suggested)
  • wait for ESPx READY_OUTPUT bit to go high (a timeout is suggested)
  • Read the ESPx IO port
  • it is a best practice to wait for ESPx BUSY bit to go high then low (a timeout is suggested) before sending the next byte

Note that the BUSY bit transitions after a command is written or data is read can happen very fast. On slower systems a timeout is required as it is possible for the host system to miss this transition if it is not polling fast enough.

It is also a best practice to empty the ESP send buffer before sending an opcode that returns data.

For example code, see the ESPTEST.ASM program in this repo.

ESP32 ESP0 Opcode Reference

ESP32 Misc Opcodes

OP CODE Description Values
00 NO OPERATION NONE

The NO OPERATION opcode is used to sync the ESP32 communications stream to a known state, "Waiting for opcode".

Input Parameters: None
Returns: None

OP CODE Description Values
255 DISCOVER "E" "S" "P" "3" "2" "V" "1"

The DISCOVER opcode is used by host systems to verify the presence and version of the ESP hardware and firmware.

Input Parameters: None
Returns: 7 bytes - "E" "S" "P" "3" "2" "V" "1"

ESP32 Terminal Opcodes

OP CODE Description Values
1 VGA ANSI TERM OUT SINGLE CHAR OUT-BYTE

The VGA ANSI TERM OUT SINGLE CHAR opcode sends a single byte to the ANSI terminal subsystem of the ESP32. Using the ANSI escape sequence set, this byte is rendered to the VGA terminal console.

Input Parameters: 1 byte - "OUT CHAR"
Returns: None

OP CODE Description Values
2 VGA ANSI TERM OUT NULL TERMINATED STRING OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE … … … … NULL

The VGA ANSI TERM OUT NULL TERMINATED STRING opcode sends a null terminated string to the ANSI terminal subsystem of the ESP32. Using the ANSI escape sequence set, this string is rendered to the VGA terminal console.

Input Parameters: X bytes - string terminated by a null
Returns: None

OP CODE Description Values
3 VGA ANSI TERM KEYBOARD IN IN-BYTE

The VGA ANSI TERM KEYBOARD IN opcode returns a byte from the terminal keyboard buffer. If there is no keystrokes in the buffer, the opcode will return a null.

Input Parameters: None
Returns: 1 byte - input keystroke or null

OP CODE Description Values
4 VGA ANSI TERM KEYBOARD BUFFER LENGTH IN-BYTE

The VGA ANSI TERM KEYBOARD BUFFER LENGTH opcode returns the numbser of keystrokes in the ANSI terminal keyboard buffer.

Input Parameters: None
Returns: 1 byte - keystroke buffer length

OP CODE Description Values
5 VGA ANSI TERM SET CURSOR OUT-BYTE

The VGA ANSI TERM SET CURSOR opcode sets the visibility of the terminal cursor.

  • 0 = cursor off
  • 1 = cursor on

Input Parameters: 1 byte - Cursor status
Returns: None

ESP32 Serial Opcodes

OP CODE Description Values
6 Set Baud Rate OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Baud Rate opcode sets the baud rate for the ESP async serial port. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module. Byte order is least signifigant byte to most significant byte.

Input Parameters: 4 bytes - Baud Rate Returns: None

OP CODE Description Values
7 Set Serial Mode OUT-BYTE

The Set Serial Mode opcode sets the serial communication parameters for the ESP async serial port. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module. Parameters are set as follows:

  • 0 = 8 data bits, no parity, 1 stop bits
  • 1 = 8 data bits, even parity, 1 stop bits
  • 2 = 8 data bits, odd parity, 1 stop bits
  • 3 = 7 data bits, no parity, 1 stop bits
  • 4 = 7 data bits, even parity, 1 stop bits
  • 5 = 7 data bits, odd parity, 1 stop bits

Input Parameters: 1 byte - Serial Mode
Returns: None

OP CODE Description Values
8 Serial TX Single char OUT-BYTE

The Serial TX Single char opcode transmits a single byte through the serial communication port. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: 1 byte - char
Returns: None

OP CODE Description Values
9 Serial TX Null Terminated String OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE … … … … NULL

The Serial TX Null Terminated String opcode transmits a null terminated string through the serial communication port. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: X bytes - string terminated by a null
Returns: None

OP CODE Description Values
10 Serial RX IN-BYTE

The Serial RX opcode returns a byte from the serial communication port buffer. If there are no values in the buffer, the opcode will return a null. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: None
Returns: 1 byte - input value or null

OP CODE Description Values
11 Chars in Serial Buffer IN-BYTE

The Chars in Serial Buffer opcode returns the numbser of keystrokes in the serial communication port buffer. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: None
Returns: 1 byte - serial buffer length

ESP32 Audio Opcodes

OP CODE Description Values
12 Play Null Terminated String OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE … … … … NULL

The Play Null Terminated String opcode intreprets a string as musical notes and plays them with a square wave tone generator through the audio port on the top of the ESP32 card. The audio port is at line level and requires amplification.

Example string: "A4 4 2 A4 4 2 A#4 4 2 C5 4 2 C5 4 2 A#4 4 2 A4 4 2 G4 4 2 F4 4 2 F4 4 2 G4 4 2 A4 4 2 A4 2 2 G4 16 2 G4 2 2 P 8 2 "

The string is in the format: [note (C,D,E,F,G,A,B) + [#,b] + octave (2..7) + space + tempo (99..1)] + [pause (P) + space + tempo (99.1)]

    "A4 4 2" 
     |  | |----- Tempo
     |  |------- Octave (2..7)
     |---------- note to play (or P for pause)

Input Parameters: 1 byte - Cursor status
Returns: None

OP CODE Description Values
13 Play Sound OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Play Sound opcode plays a sound with the specified parameters through the audio port on the top of the ESP32 card. The audio port is at line level and requires amplification.

The following parameters need to be specified in the following order:

  • Attack, 4 bytes, Byte order is least signifigant byte to most significant byte.
  • Decay, 4 bytes, Byte order is least signifigant byte to most significant byte.
  • Sustain, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Release, 4 bytes, Byte order is least signifigant byte to most significant byte.
  • WaveType, 1 byte, 0=WAVE_SQUARE,1=WAVE_SINE,2=WAVE_TRIANGLE,3=WAVE_SAW,4=WAVE_NOISE
  • Volume, 2 bytes, Byte order is least signifigant byte to most significant byte. Even though volume is specified as two bytes, only LSB is used.
  • Duration, 2 bytes, Byte order is least signifigant byte to most significant byte. Duration is in MS.
  • FreqStart, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • FreqEnd, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • ModFreqMode, 1 byte, 0=MODFREQ_NONE,1=MODFREQ_TO_END,2=MODFREQ_TO_RELEASE,3=MODFREQ_TO_SUSTAIN

More detailed information about programming the sound generator can be found HERE

Input Parameters: 24 bytes Returns: None

OP CODE Description Values
14 Set Volume OUT-BYTE

The Set Volume opcode sets the overall volume of the sound generated by the audio port on the top of the ESP32 card. The audio port is at line level and requires amplification.

Input Parameters: 1 byte - Volume Returns: None

ESP32 Graphics Opcodes

OP CODE Description Values
15 Set Display Resolution OUT-BYTE

The Set Display Resolution opcode sets the display resolution of the VGA output of the ESP32. The specified display resolution is stored in flash memory and will survive a power cycle. Note that this opcode can take a SECOND OR MORE to process as it requires the ESP to reboot, so leave plenty of time after issuing this command. ALWAYS issue a Clear Display(17) command after changing video mode.

The proper sequence is as follows:

  • issue Set Display Resolution opcode
  • send one byte for new video mode
  • wait at least 3 seconds
  • issue clear display command
ID Mode Name Description Color Depth
00 VGA_320x200_70Hz 320x200@70Hz resolution - the same of VGA_640x200_70Hz with horizontal halved 64
01 VGA_320x200_75Hz 320x200@75Hz resolution 64
02 VGA_320x200_75HzRetro 320x200@75Hz retro resolution 64
03 QVGA_320x240_60Hz 320x240@60Hz resolution 64
04 VGA_400x300_60Hz 400x300@60Hz resolution 64
05 VGA_480x300_75Hz 480x300@75Hz resolution 64
06 VGA_512x192_60Hz 512x192@60Hz resolution 16
07 VGA_512x384_60Hz 512x384@60Hz resolution 16
08 VGA_512x448_60Hz 512x448@60Hz resolution 16
09 VGA_512x512_58Hz 512x512@58Hz resolution 16
10 VGA_640x200_60HzD 640x200@60Hz doublescan resolution 16
11 VGA_640x200_70Hz 640x200@70Hz resolution - the same of VGA_640x400_70Hz with vertical halved 16
12 VGA_640x200_70HzRetro 640x200@70Hz retro resolution 16
13 VGA_640x240_60Hz 640x240@60Hz (DoubleScan) resolution 16
14 VGA_640x350_70Hz 640x350@70Hz resolution 16
15 VGA_640x350_70HzAlt1 640x350@70HzAlt1 resolution 16
16 VESA_640x350_85Hz 640x350@85Hz resolution 16
17 VGA_640x382_60Hz 640x382@60Hz resolution 16
18 VGA_640x384_60Hz 640x384@60Hz resolution 16
19 VGA_640x400_70Hz 640x400@70Hz resolution 16
20 VGA_640x400_60Hz 640x400@60Hz (actually 640x480 but with less lines) 16
21 VGA_640x480_60Hz 640x480@60Hz resolution 16
22 VGA_640x480_60HzAlt1 640x480@60HzAlt1 resolution 16
23 VGA_640x480_60HzD 640x480@60Hz doublescan resolution 16
24 VGA_640x480_73Hz 640x480@73Hz resolution 16
25 VESA_640x480_75Hz 640x480@75Hz resolution 16
26 VGA_720x348_50HzD 720x348@50Hz doublescan resolution 16
27 VGA_720x348_59HzD 720x348@59Hz doublescan resolution 16
28 VGA_720x348_73Hz 720x348@73Hz resolution 16
29 VGA_720x350_70Hz 720x350@70Hz resolution 16
30 VGA_720x400_70Hz 720x400@70Hz resolution 16
31 VESA_720x400_85Hz 720x400@85Hz resolution 16
32 PAL_720x576_50Hz 720x576@50Hz resolution 8
33 VESA_768x576_60Hz 768x576@60Hz resolution 8
34 SVGA_800x300_60Hz 800x300@60Hz resolution 8
35 SVGA_800x600_56Hz 800x600@56Hz resolution 4
36 SVGA_800x600_60Hz 800x600@60Hz resolution 4
37 SVGA_960x540_60Hz 960x540@60Hz resolution 4
38 SVGA_1024x768_60Hz 1024x768@60Hz resolution 2
39 SVGA_1024x768_70Hz 1024x768@70Hz resolution 2
40 SVGA_1024x768_75Hz 1024x768@75Hz resolution 2
41 SVGA_1280x600_60Hz 1280x600@60Hz resolution 2
42 SVGA_1280x720_60Hz 1280x720@60Hz resolution 2
43 SVGA_1280x720_60HzAlt1 1280x720@60Hz resolution 2
44 SVGA_1280x768_50Hz 1280x768@50Hz resolution 2

Input Parameters: 1 byte - Video Mode Returns: None

OP CODE Description Values
16 Load Font OUT-BYTE

The Load Font opcode sets the display font for the VGA ANSI Terminal.

ID Font Name
00 FONT_4X6
01 FONT_5X7
02 FONT_5X8
03 FONT_6X8
04 FONT_6X9
05 FONT_6X10
06 FONT_6X12
07 FONT_6X13
08 FONT_7X13
09 FONT_7X14
10 FONT_8X8
11 FONT_8X9
12 FONT_8X13
13 FONT_8X14
14 FONT_8X16
15 FONT_8X19
16 FONT_9X15
17 FONT_9X18
18 FONT_10X20
19 FONT_BIGSERIF_8X14
20 FONT_BIGSERIF_8X16
21 FONT_BLOCK_8X14
22 FONT_BROADWAY_8X14
23 FONT_COMPUTER_8X14
24 FONT_COURIER_8X14
25 FONT_LCD_8X14
26 FONT_OLDENGL_8X16
27 FONT_SANSERIF_8X14
28 FONT_SANSERIF_8X16
29 FONT_SLANT_8X14
30 FONT_WIGGLY_8X16

Input Parameters: 1 byte - Font Returns: None

OP CODE Description Values
17 Clear Display NONE

The Clear Display opcode clears the VGA.

Input Parameters: None Returns: None

OP CODE Description Values
18 Copy Rectangle OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Copy Rectangle opcode copyies a rectangle shaped area from one part of the bitmapped display to another.

The following parameters need to be specified in the following order:

  • Source X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Source Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Destination X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Destination Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Area Width, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Area Hight, 2 bytes, Byte order is least signifigant byte to most significant byte.

All Parameters above are in display pixels with 0,0 being the upper left of the VGA screen.

Input Parameters: 12 bytes Returns: None

OP CODE Description Values
19 Draw Bitmap OUT-BYTE(s)

The Draw Bitmap opcode draws a specified bitmap on the VGA display.

The following parameters need to be specified in the following order:

  • X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Width, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Hight, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Pixel Format, 1 byte, FORMAT=1:NATIVE DEVICE(usually 1 BIT/PIXEL),2:MASK(1=OPAQUE 0=TRANSP),3: 8 BITS/PIXEL aabbggrr, 4:32 BITS/PIXEL RGBA
  • Bitmap Length, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Bitmap Data, X bytes, bitmap size cannot exceed 31.5K

Input Parameters: X bytes Returns: None

OP CODE Description Values
20 Draw Char OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Draw Char opcode draws a specified character, at a specified location, in a specified font, in the current Pen color.

The following parameters need to be specified in the following order:

  • X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Character to Draw, 1 byte
  • Font, 1 bytes, See Font Table from Set Font opcode

Input Parameters: 6 bytes Returns: None

OP CODE Description Values
21 Draw Ellipse OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Draw Ellipse opcode draws an ellpise on the bitmapped display, in the current Pen color.

The following parameters need to be specified in the following order:

  • X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Width, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Height, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 6 bytes Returns: None

OP CODE Description Values
22 Draw Gliph OUT-BYTE(s)

The Draw Glyph opcode draws a Glyph on the bitmapped display, in the current Pen color.

The following parameters need to be specified in the following order:

  • X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Width, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Height, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Index, 2 bytes, Byte order is least signifigant byte to most significant byte. Usually 0, Use when the buffer contains multiple glyphs.
  • Glyph Length, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Glyph Data, X bytes, glyph size cannot exceed 255 bytes, and is stored as a 1 bit/pixel bitmap

Input Parameters: X bytes Returns: None

OP CODE Description Values
23 Draw Line OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Draw Line opcode draws a line on the bitmapped display, in the current Pen color.

The following parameters need to be specified in the following order:

  • Start X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Start Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 8 bytes Returns: None

OP CODE Description Values
24 Draw Rectangle OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Draw Rectangle opcode draws a Rectangle on the bitmapped display, in the current Pen color.

The following parameters need to be specified in the following order:

  • Start X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Start Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 8 bytes Returns: None

OP CODE Description Values
25 Draw Filled Ellipse OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Draw Filled Ellipse opcode draws a filled ellipse on the bitmapped display, in the current Pen color, filled with the current Brush color.

The following parameters need to be specified in the following order:

  • Start X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Start Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • width, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Height, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 8 bytes Returns: None

OP CODE Description Values
26 Draw Filled Rectangle OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Draw Filled Rectangle opcode draws a filled rectangle on the bitmapped display, in the current Pen color, filled with the current Brush color.

The following parameters need to be specified in the following order:

  • Start X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Start Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 8 bytes Returns: None

OP CODE Description Values
27 Get Pixel Value OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE IN-BYTE IN-BYTE IN-BYTE

The Get Pixel Value opcode returns the current color value of the specified display pixel.

The following parameters need to be specified in the following order:

  • X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

The ESP will then return:

  • Blue value, 1 byte
  • Green value, 1 byte
  • Red value, 1 byte

Input Parameters: 4 bytes Returns: 3 bytes

OP CODE Description Values
28 Invert Rectangle OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Invert Rectangle opcode will invert all of the pixels within a specified area on the bitmapped display.

The following parameters need to be specified in the following order:

  • Start X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Start Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 8 bytes Returns: None

OP CODE Description Values
29 Draw A Line To OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Draw A Line To opcode will draw a line from the current graphics cursor position to the specified location on the bitmapped display.

The following parameters need to be specified in the following order:

  • End X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 4 bytes Returns: None

OP CODE Description Values
30 Move Cursor To OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Move Cursor To opcode will move the graphics cursor to the specified location on the bitmapped display.

The following parameters need to be specified in the following order:

  • End X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 4 bytes Returns: None

OP CODE Description Values
31 Scroll Display OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Scroll Display opcode will scroll the display by the specified offset.

The following parameters need to be specified in the following order:

  • X Offset, 2 bytes, Byte order is least signifigant byte to most significant byte. Left Scroll is accomplished by a negative offset
  • Y Offset, 2 bytes, Byte order is least signifigant byte to most significant byte. Up Scroll is accomplished by a negative offset

Input Parameters: 4 bytes Returns: None

OP CODE Description Values
32 Set Brush Color OUT-BYTE

The Set Brush Color sets the brush color to the specified color index on the pallette.

Input Parameters: 1 byte - Color Returns: None

OP CODE Description Values
33 Set Line Ends OUT-BYTE

The Set Line Ends sets the method for drawing line ends by the display renderer.

  • 0=NONE
  • 1=ROUNDED

Input Parameters: 1 byte - End Type Returns: None

OP CODE Description Values
34 Set Pen Color OUT-BYTE

The Set Pen Color sets the brush color to the specified color index on the pallette.

Input Parameters: 1 byte - Color Returns: None

OP CODE Description Values
35 Set Pen Width OUT-BYTE

The Set Pen Width sets the width in pixels of the drawing pen.

Input Parameters: 1 byte - Pen Width Returns: None

OP CODE Description Values
36 Set Pixel OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Pixel draws a pixel at the specified location in the current pen color.

The following parameters need to be specified in the following order:

  • End X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • End Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 4 bytes Returns: None

OP CODE Description Values
37 Set Glyph Options OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Glpyh Options opcode sets optional parameters that modify how glyphs are rendered by Draw Glyph.

The following parameters need to be specified in the following order:

  • blank, 1 byte, send 1 to cause glyph to be rendered in background color
  • bold, 1 byte, send 1 to cause glyph to be rendered in bold
  • doubleWidth, 1 byte, send 1 to cause glyph to be rendered double width
  • FillBackground, 1 byte, send 1 to cause glyph to be rendered with background painted in the specified brush color
  • Invert, 1 byte, send 1 to cause glyph to be rendered inverted
  • Italic, 1 byte, send 1 to cause glyph to be rendered in italics
  • Underline, 1 byte, send 1 to cause glyph to be rendered with an underline

Input Parameters: 7 bytes Returns: None

OP CODE Description Values
38 Set Pallette Item OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Pallette Item opcode sets the rendered color for a given color index.

The following parameters need to be specified in the following order:

  • Index, 1 byte, Color Index on Pallette (0-63 or 0-15, or 0-3, or 0-2 or 0-1 depending on screen color depth)
  • Blue Value, 1 byte
  • Green Value, 1 byte
  • Red Value, 1 byte

Input Parameters: 4 bytes Returns: None

OP CODE Description Values
39 Set Mouse Cursor Type OUT-BYTE

The Set Mouse Cursor Type opcode sets the shape of the rendered mouse cursor.

ID Description
0 11x11 Amiga like colored mouse pointer
1 10x15 mouse pointer
2 11x19 mouse pointer
3 11x19 shadowed mouse pointer
4 12x17 mouse pointer
5 16x16 pen
6 9x9 cross
7 11x11 cross
8 5x5 point
9 11x11 left arrow
10 11x11 right arrow
11 11x11 down arrow
12 11x11 up arrow
13 19x19 move
14 12x12 resize orientation 1
15 12x12 resize orientation 2
16 11x17 resize orientation 3
17 17x11 resize orientation 4
18 7x15 text input

Input Parameters: 1 byte - Mouse Cursor Type Returns: None

OP CODE Description Values
40 Set Mouse Cursor Position OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Mouse Cursor Position opcode sets the display position of the mouse cursor.

The following parameters need to be specified in the following order:

  • X coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Y coordinate, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 4 bytes Returns: None

OP CODE Description Values
41 Clear Sprites NONE

The Clear Sprites opcode clears the sprite shape table.

Input Parameters: None
Returns: None

OP CODE Description Values
42 Set Sprite Map OUT-BYTE(s)

setSpriteMap 42 *AWAYS SET THE HIGHEST INDEX SPRITE LAST, AND THE MAX CONFIGURED SPRITE NUMBER IS 31. (0-32)

The Set Sprite Map opcode sets the shape for a specified sprite. There are 32 sprites (0-31) available with the current firmware and it is important to set the highest # sprite used LAST.

The following parameters need to be specified in the following order:

  • Sprite Index, 1 byte
  • Sprite Width, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Sprite Hight, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Pixel Format, 1 byte, FORMAT=1:NATIVE DEVICE(usually 1 BIT/PIXEL),2:MASK(1=OPAQUE 0=TRANSP),3: 8 BITS/PIXEL aabbggrr, 4:32 BITS/PIXEL RGBA
  • Sprite Length, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Sprite Data, X bytes, bitmap size cannot exceed 31.5K

Input Parameters: X bytes Returns: None

OP CODE Description Values
43 Set Sprite Location OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Sprite Location opcode moves a specified sprite to a specified location.

The following parameters need to be specified in the following order:

  • X Coordinate Location, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Y Coordinate Location, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Sprite Index, 1 byte

Input Parameters: 5 bytes Returns: None

OP CODE Description Values
44 Set Sprite Visibility OUT-BYTE OUT-BYTE

The Set Sprite Visibility opcode sets the visibility of a specified sprite.

The following parameters need to be specified in the following order:

  • Sprite Index, 1 byte
  • Visible, 1 byte, 0= hidden, 1=visible

Input Parameters: 2 bytes Returns: None

ESP32 ESP1 Opcode Reference

ESP32 Misc Opcodes

OP CODE Description Values
00 NO OPERATION NONE

The NO OPERATION opcode is used to sync the ESP32 communications stream to a known state, "Waiting for opcode".

Input Parameters: None
Returns: None

OP CODE Description Values
255 DISCOVER "E" "S" "P" "3" "2" "V" "1"

The DISCOVER opcode is used by host systems to verify the presence and version of the ESP hardware and firmware.

Input Parameters: None
Returns: 7 bytes - "E" "S" "P" "3" "2" "V" "1"

ESP32 WiFi Opcodes

OP CODE Description Values
1 WiFi Set SSID OUT-BYTE(s)

The WiFi Set SSID opcode stores a null terminated string in the ESP flash memory and will survive a power cycle. This value is then used during WiFi Connection.

Input Parameters: X bytes - string terminated by a null
Returns: None

OP CODE Description Values
2 WiFi Set Password OUT-BYTE(s)
The WiFi Set WiFi Password opcode stores a null terminated string in the ESP flash memory and will survive a power cycle. This value is then used during WiFi Connection.

Input Parameters: X bytes - string terminated by a null
Returns: None

OP CODE Description Values
3 WiFi Connect None

The WiFi Connect opcode will attempt to connect to a WiFI access point using the stored configuration information. If No TCP/IP address information is configured, DHCP will be attempted.

Input Parameters: None
Returns: None

OP CODE Description Values
4 WiFi Get Status IN-BYTE

The WiFi Get Status opcode returns the current WiFi status.

Status Byte Description
0 WL_IDLE_STATUS
1 WL_NO_SSID_AVAIL
2 WL_SCAN_COMPLETED
3 WL_CONNECTED
4 WL_CONNECT_FAILED
5 WL_CONNECTION_LOST
6 WL_DISCONNECTED

Input Parameters: None
Returns: 1 byte - WiFi Status

OP CODE Description Values
5 WiFi Get Signal Strength IN-BYTE

The WiFi Get Signal Strength opcode returns the current WiFi signal strength.

Input Parameters: None
Returns: 1 bytes- Signal Strength

ESP32 TCP/IP Opcodes

OP CODE Description Values
12 Get IP Address IN-BYTE IN-BYTE IN-BYTE IN-BYTE

The Get IP Address opcode returns the current IP address.

Input Parameters: None
Returns: 4 bytes (octet 1,2,3,4)

OP CODE Description Values
13 Get Subnet Mask IN-BYTE IN-BYTE IN-BYTE IN-BYTE

The Get Subnet Mask opcode returns the current submet mask.

Input Parameters: None
Returns: 4 bytes (octet 1,2,3,4)

OP CODE Description Values
14 Get Gateway IN-BYTE IN-BYTE IN-BYTE IN-BYTE

The Get Gateway opcode returns the current IP default gateway.

Input Parameters: None
Returns: 4 bytes (octet 1,2,3,4)

OP CODE Description Values
15 Get Primary DNS IN-BYTE IN-BYTE IN-BYTE IN-BYTE

The Get Primary DNS returns the current primary DNS address.

Input Parameters: None
Returns: 4 bytes (octet 1,2,3,4)

OP CODE Description Values
16 Get Secondary DNS IN-BYTE IN-BYTE IN-BYTE IN-BYTE

The Get Secondary DNS opcode returns the current secondary DNS IP address.

Input Parameters: None
Returns: 4 bytes (octet 1,2,3,4)

OP CODE Description Values
17 Set IP Address OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set IP Address opcode sets the IP address. 0.0.0.0 value enables DHCP.

Input Parameters: 4 bytes (octet 1,2,3,4)
Returns: None

OP CODE Description Values
18 Set Subnet Mask OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Subnet Mask opcode sets the subnet mask.

Input Parameters: 4 bytes (octet 1,2,3,4)
Returns: None

OP CODE Description Values
19 Set Gateway OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Gateway opcode sets the Gateway IP Address.

Input Parameters: 4 bytes (octet 1,2,3,4)
Returns: None

OP CODE Description Values
20 Set Primary DNS OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Primary DNS opcode sets the primary DNS IP address.

Input Parameters: 4 bytes (octet 1,2,3,4)
Returns: None

OP CODE Description Values
21 Set Secondary DNS OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Secondary DNS opcode sets the secondary DNS IP address.

Input Parameters: 4 bytes (octet 1,2,3,4)
Returns: None

OP CODE Description Values
22 Set Hostname OUT-BYTE(s)

The Set Hostname opcode stores a null terminated string in the ESP flash memory and will survive a power cycle. This value is then used during WiFi Connection.

Input Parameters: X bytes - string terminated by a null
Returns: None

OP CODE Description Values
23 Create Outgoing Connection OUT-BYTEs

The Create Outgoing Connection opcode creates an outgoing TCP/IP socket connection to a specified host.

The following parameters need to be specified in the following order:

  • Connection Number, 1 byte, Must be from 1-63, connection 0 is reserved for incoming connections.
  • Port, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Hostname, x bytes, null terminated string.

Input Parameters: x bytes Returns: None

OP CODE Description Values
24 Set Incoming Port OUT-BYTE OUT-BYTE

The Set Incoming Port opcode sets listen port for connection 0.

The following parameters need to be specified in the following order:

  • Port Number, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: 2 bytes Returns: None

OP CODE Description Values
25 Out Byte to Connection# OUT-BYTE OUT-BYTE

The Out Byte to Connection# opcode sends a byte to the specified connection.

The following parameters need to be specified in the following order:

  • Connetion #, 1 byte
  • Char, 1 byte

Input Parameters: 2 bytes Returns: None

OP CODE Description Values
26 Out String to Connection# OUT-BYTE OUT-BYTE(s)

The Out String to Connection# opcode sends a null terminated string to the specified connection.

The following parameters need to be specified in the following order:

  • Connetion #, 1 byte
  • string, x bytes null terminated

Input Parameters: x bytes Returns: None

OP CODE Description Values
27 In Byte From Connection# OUT-BYTE IN-BYTE

The In Byte From Connection# opcode returns a byte from the connection communication buffer. If there are no values in the buffer, the opcode will return a null.

Input Parameters: 1 byte - Connection Number
Returns: 1 byte - input value or null

OP CODE Description Values
28 Chars in Buffer from Connection# OUT-BYTE IN-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Chars in Buffer from Connection# opcode returns the numbser of bytes in the connection communication buffer. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: 1 byte - Connection Number
Returns: 1 byte - number of bytes in the buffer

OP CODE Description Values
30 Get MAC Address IN-BYTE IN-BYTE IN-BYTE IN-BYTE IN-BYTE IN-BYTE

The Get Mac Address opcode returns the six byte MAC address of the ESP32

The following information is returned in the following order:

  • MAC Address, 6 bytes

Input Parameters: None
Returns: 6 bytes

ESP32 Serial Opcodes

OP CODE Description Values
6 Set Baud Rate OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE

The Set Baud Rate opcode sets the baud rate for the ESP async serial port. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module. Byte order is least signifigant byte to most significant byte.

Input Parameters: 4 bytes - Baud Rate Returns: None

OP CODE Description Values
7 Set Serial Mode OUT-BYTE

The Set Serial Mode opcode sets the serial communication parameters for the ESP async serial port. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module. Parameters are set as follows:

  • 0 = 8 data bits, no parity, 1 stop bits
  • 1 = 8 data bits, even parity, 1 stop bits
  • 2 = 8 data bits, odd parity, 1 stop bits
  • 3 = 7 data bits, no parity, 1 stop bits
  • 4 = 7 data bits, even parity, 1 stop bits
  • 5 = 7 data bits, odd parity, 1 stop bits

Input Parameters: 1 byte - Serial Mode
Returns: None

OP CODE Description Values
8 Serial TX Single char OUT-BYTE

The Serial TX Single char opcode transmits a single byte through the serial communication port. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: 1 byte - char
Returns: None

OP CODE Description Values
9 Serial TX Null Terminated String OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE OUT-BYTE … … … … NULL

The Serial TX Null Terminated String opcode transmits a null terminated string through the serial communication port. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: X bytes - string terminated by a null
Returns: None

OP CODE Description Values
10 Serial RX IN-BYTE

The Serial RX opcode returns a byte from the serial communication port buffer. If there are no values in the buffer, the opcode will return a null. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: None
Returns: 1 byte - input value or null

OP CODE Description Values
11 Chars in Serial Buffer IN-BYTE

The Chars in Serial Buffer opcode returns the numbser of keystrokes in the serial communication port buffer. This port is exposed through the header on the top of the card and through the USB port on the ESP32 module.

Input Parameters: None
Returns: 1 byte - serial buffer length

ESP32 Mouse Opcodes

OP CODE Description Values
29 Get Mouse IN-BYTE IN-BYTE IN-BYTE IN-BYTE IN-BYTE IN-BYTE IN-BYTE IN-BYTE

GetMouse 29 left btn middle btn right btn Wheel Delta X X Y Y

The Get Mouse opcode gets the current mouse information.

The following information is returned in the following order:

  • Left Button Status, 1 byte
  • Middle Button Status, 1 byte
  • Right Button Status, 1 byte
  • Wheel location Delta, 1 byte
  • X Coordinate Location, 2 bytes, Byte order is least signifigant byte to most significant byte.
  • Y Coordinate Location, 2 bytes, Byte order is least signifigant byte to most significant byte.

Input Parameters: None
Returns: 8 bytes

TO DO

  • Improve formatting of README file
  • Complete espconf program
  • add better status messages to testesp.c
  • add API for getting the MAC address