Matrix Display (ESP32 + FATEK RS232 Protocol + HUB75)

This project reads data from a FATEK PLC over the FATEK RS232 communication protocol and shows status messages on a HUB75 LED matrix panel.

The firmware runs on ESP32 and uses two FreeRTOS tasks:

• one task for PLC communication;
• one task for LED matrix rendering.

What This Application Does

• Reads PLC coils and registers (M, D, R) through FATEK RS232 protocol commands.
• Computes and uses LRC checksum for FATEK RS232 frame validation.
• Converts selected register ranges into text.
• Chooses a display scenario based on PLC state.
• Shows 3-line messages with centered text and smooth scrolling.
• Detects PLC communication timeout and shows error status.

Scenario Priority and Hierarchy

The firmware always shows only one active scenario, based on this priority order (top = highest priority):

1. Scenario 6 - Communication error
   Condition: PLC communication timeout.
   Display: Acest post este INDISPONIBIL E0

2. Scenario 7 - Unavailable
   Condition: M120 = 0 (only when communication is OK).
   Display: Acest post este INDISPONIBIL E1

3. Scenario 5 - Pause finished
   Condition: M99 = 1 and D0 > 0.

4. Scenario 4 - Pause
   Condition: M97 = 1 and D0 > 0.

5. Scenario 3 - Function display
   Condition: M94 = 1, exactly one of M71..M79 = 1, and D0 > 0.

6. Scenario 1 / 1.1 / 1.2 - Welcome states (D0 = 0)

   • Scenario 1: M320 = 1
   • Scenario 1.1: M322 = 1
   • Scenario 1.2: M321 = 1
     Internal text selection order in code: 1.2 -> 1.1 -> 1.

7. Scenario 2 - Amount introduced
   Condition: D0 > 0 (used when higher-priority scenarios are not active).

Some lines are static and some lines scroll from right to left, based on scenario and text length.

FATEK Registers Used and Where They Are Used

M Coils (Discrete Relays)

• M71..M79 (0x817..0x81F): select active function group in Scenario 3 (exactly one active).
• M94 (0x82E): enables Scenario 3 logic.
• M97 (0x831): enables Scenario 4 (Pause).
• M99 (0x833): enables Scenario 5 (Pause finished).
• M120 (0x848): availability flag (0 -> Scenario 7 unavailable message).
• M320 (0x910): Scenario 1 (welcome + minimum amount).
• M321 (0x911): Scenario 1.2 (welcome variant with Boxa + ATM message).
• M322 (0x912): Scenario 1.1 (welcome variant with tokens message).

D Registers (Data Registers)

• D0 (0x1770): core amount/status condition (D0 = 0 for welcome states, D0 > 0 for amount-based states).
• D10 (0x177A): used in Scenario 1 to build minimum X Lei/Leu.
• D47..D49 (0x179F..0x17A1): time/value formatting for Scenario 3 and Scenario 5.
• D57..D59 (0x17A9..0x17AB): time/value formatting for Scenario 4.

R Registers (Holding Registers)

• Used ranges: R10..R99 (0x0A..0x63) and R110..R199 (0x6E..0xC7).
• These registers hold ASCII text payload for Scenario 3.
• Mapping by active M bit:
  • M71 -> line 1 from R10..R19, line 2 from R110..R119
  • M72 -> line 1 from R20..R29, line 2 from R120..R129
  • M73 -> line 1 from R30..R39, line 2 from R130..R139
  • M74 -> line 1 from R40..R49, line 2 from R140..R149
  • M75 -> line 1 from R50..R59, line 2 from R150..R159
  • M76 -> line 1 from R60..R69, line 2 from R160..R169
  • M77 -> line 1 from R70..R79, line 2 from R170..R179
  • M78 -> line 1 from R80..R89, line 2 from R180..R189
  • M79 -> line 1 from R90..R99, line 2 from R190..R199

Colors Used

The display uses RGB colors from code (via color565 conversion):

• White: (255, 255, 255) for welcome messages (Scenarios 1/1.1/1.2)
• Light green: (128, 255, 128) for Scenario 2
• Red: (255, 0, 0) for Scenarios 6 and 7
• Orange: (255, 128, 0) for Scenario 4 title
• Pink: (255, 128, 128) for Scenario 5 title lines
• Blue accent: (128, 128, 255) for time lines in Scenarios 3/4/5

Scenario 3 line colors by function bit:

• M71: (0, 255, 128)
• M72: (0, 128, 255)
• M73: (255, 0, 255)
• M74: (0, 255, 255)
• M75: (128, 255, 0)
• M76: (255, 0, 128)
• M77: (128, 0, 255)
• M78: (0, 255, 0)
• M79: (255, 255, 0)

Hardware and Communication

• MCU: ESP32
• PLC link: FATEK communication protocol over RS232
• Matrix: HUB75, configured as 64x32, chain 1
• HUB75 to ESP32 pin mapping used in this project:
  • R1 -> GPIO25
  • G1 -> GPIO26
  • B1 -> GPIO27
  • R2 -> GPIO14
  • G2 -> GPIO12
  • B2 -> GPIO13
  • A -> GPIO23
  • B -> GPIO19
  • C -> GPIO18
  • D -> GPIO5
  • E -> -1 (not used for current panel setup)
  • LAT -> GPIO32
  • OE -> GPIO15
  • CLK -> GPIO33
• RS232 serial defaults in code:
  • RX: 16
  • TX: 17
  • Baud: 115200
  • UART format: 7E1 (SERIAL_7E1)
  • Station/Slave ID default: 1
  • Request timeout: 2000 ms
  • Communication timeout status threshold: 3000 ms

For deeper technical details about FATEK register maps, address models, and protocol-level behavior, use the manuals in Manuale/ (summarized below).

Documentation (Manuale/)

This folder keeps offline PDFs, ZIP archives, wiring notes, and reference projects for FATEK serial protocols, PLC programming, and related hardware. Use it when you need the official framing, command codes, register/converter addressing, or connection details beyond what this README summarizes.

FATEK PLC communication (most relevant for this firmware)

Document	What it is for
08_M_PLC_Binary_Communication_Protocol_User_Manual_en.pdf	Primary reference: FATEK PLC binary / serial communication protocol (frames, commands, usage). Aligns with how this project talks to the PLC over RS232-style serial.
Chapter_12.pdf, Appendix1.pdf, Apendix 2.pdf	Supplementary chapters / appendices (protocol and addressing detail—check TOC inside each PDF).
Manuale/Comunicare/FATEK manuals/Manual_1_All_en.zip, Manual_2_All_en.zip	Bundled FATEK manual collections (English); unzip locally for full PLC/system documentation.
Manuale/Comunicare/FATEK manuals/WinProladder_Manual_en.pdf	WinProladder programming environment reference.

RS232 sample / protocol helpers (aligned with this repo)

Path	What it is for
Manuale/Comunicare/RS232 ASCII Fatek communication protocol/FatekSimpleTest/	Small Arduino-style example (FatekSimpleTest.ino) plus LRC_checksum helpers—useful cross-check for framing/LRC behaviour vs main/LRC_checksum.*.

Hardware datasheets & installation

Document	What it is for
trs3232e.pdf	RS-232 line driver/receiver IC datasheet (level shifting / UART ↔ RS232).
MT8072iP_Datasheet_ENG.pdf, GME871P30_MT8072iP_Installation_221019.pdf	HMI / panel datasheet and installation notes.
FATEK_FB_FBs_B1_B1z.pdf	FATEK FB documentation (PLC instruction/function blocks—PLC-side programming reference).

Modbus RTU / RS485 (reference only—this project uses FATEK RS232, not Modbus here)

For comparison, troubleshooting serial buses in general, or work on sibling RS485 projects, see Manuale/Comunicare/Curs ModBus RTU/ (Modbus overview, addressing, function codes, troubleshooting PDFs) and Manuale/Comunicare/RS485 proiect/ (RS485 wiring images, MAX485 datasheet, Modbus specification excerpts, older firmware snippets).

Diagrams & photos (Manuale/ root)

• Rs232.png, RS232 - banana.jpg, Rs485 COM.png — quick visual references for serial interfaces.

Note: Large binaries under Manuale/ may not be suitable for every Git host; if you mirror only source code elsewhere, copy Manuale/ separately or rely on official FATEK downloads.

Project Structure

• main/main.ino - main firmware, scenario logic, display rendering, task creation.
• main/FATEKRS232.h - RS232 data structures and public API.
• main/FATEKRS232.cpp - FATEK RS232 polling, parsing, communication state, register decoding.
• main/LRC_checksum.h - LRC checksum declarations.
• main/LRC_checksum.cpp - LRC checksum implementation used by FATEK RS232 frames.
• registrii FATEK utilizati.txt - register usage reference.
• culori folosite.txt - color reference notes.
• Manuale/ - manuals, datasheets, and communication reference materials (see Documentation (Manuale/) above).

Wiring and Reference Images

Store the reference images in img/ (project root), then they will render directly in this README.

HUB75 Connector

ESP32 Pinout (NODE32S)

ESP32 Dev Board 10 Pinout

HUB75 Port Orientation Used

Dependencies

This project uses:

• ESP32-HUB75-MatrixPanel-I2S-DMA (HUB75 library) - MIT
• Arduino Core for ESP32 (Arduino/ESP32 framework) - LGPL-2.1

Build and Run Notes

• Open the project in Arduino IDE or PlatformIO with ESP32 support.
• Select the correct ESP32 board and serial port.
• Verify RS232 electrical level compatibility with ESP32 UART (use a proper transceiver/adapter when required).
• Upload firmware and monitor serial output at 115200 if Serial Monitor debug is enabled.

License

This repository is licensed under GNU General Public License v3.0 (GPL-3.0).

See the full license text in the LICENSE file.

Third-Party License Notes and Credits

This project depends on third-party software with compatible licenses:

• HUB75 library (ESP32-HUB75-MatrixPanel-I2S-DMA) - MIT License - GitHub
• Arduino core/framework parts - LGPL-2.1 - GitHub

Compatibility note:

• MIT-licensed code is compatible with GPL-3.0 and can be used in a larger GPL project.
• LGPL components are compatible with this project structure and usage model.

Important obligations kept by this project:

• Original copyright/license notices from dependencies should be preserved.
• Third-party license terms remain valid for their own code parts.
• This project-level license (GPL-3.0) applies to the project as distributed.