# shimanto008/master-slave-dice-roller architecture
> Architecture diagram of the GitHub repository shimanto008/master-slave-dice-roller, generated by GitDiagram from its file tree, README and a sample of source files (last updated 2026-06-16). It is an AI-made overview: check details against the source.
- Interactive diagram: https://gitdiagram.com/shimanto008/master-slave-dice-roller
- Repository: https://github.com/shimanto008/master-slave-dice-roller
## Overview
1. **What this repository is**
- This is a **simulation-oriented embedded systems project**, not an application server or desktop app.
- The core architecture is a **two-node ATmega32 system**: one MCU acts as **Master**, the other as **Slave**, connected by **USART serial communication** and executed in **Proteus 8**.
2. **Top-level repository boundary**
- The repository is split into three meaningful parts:
- **Master firmware** source and build outputs
- **Slave firmware** source and build outputs
- **Proteus circuit design** that wires both MCUs and their peripherals together
- The committed `.hex` files are part of the runtime deployment path for Proteus simulation.
3. **Master MCU subsystem**
- The **Master ATmega32** owns the actual game logic.
- Its inputs/outputs are:
- **Push button on PD2 / INT0** for dice rolls
- **7-segment display on PORTC** for the current dice value
- **Three LEDs on PB0/PB1/PB2** for game-status signaling
- **USART TX on PD1** to send game events to the Slave
- This side is the control plane of the system.
4. **Slave MCU subsystem**
- The **Slave ATmega32** is a display-only companion.
- It receives serial data on **PD0 / RXD** and renders the **roll history and status messages** on a **16x2 HD44780-compatible LCD**.
- It does not drive the game state; it mirrors the Master’s updates.
5. **Data flow between the two MCUs**
- The main architectural boundary is a **one-way Master → Slave data stream**.
- Every roll event is packaged into a **5-byte USART frame**:
- start marker `0xFF`
- dice value
- player ID
- status byte
- end marker `0xFE`
- This framing is the key interface to diagram, because it defines how state leaves the Master and becomes display data on the Slave.
6. **Game-state behavior**
- The Master implements the turn rules:
- **1–5** ends the turn
- **6** grants an extra turn
- **two 6s in a row** continues the bonus sequence
- **three 6s in a row** eliminates the turn and resets the sequence
- These states are encoded into the **status byte** and reflected physically by the LEDs and logically by the serial packet.
7. **User interaction path**
- The user interacts with the system only through the **Master-side push button**.
- A button press triggers a dice roll, which updates:
- the Master’s local outputs immediately
- the serial packet sent to the Slave
- There is no direct user input on the Slave side.
8. **Display responsibilities are intentionally separated**
- The **Master** shows the instantaneous dice result on the **7-segment display** and status via LEDs.
- The **Slave** accumulates and formats the **roll history** on the LCD, such as player roll sequences and messages like “Roll Again!”, “Turn Done!”, or “ELIMINATED!”.
- This separation makes the diagram clearer: one MCU handles **real-time game control**, the other handles **session history display**.
9. **Hardware / simulation layer**
- Both MCUs run at **8 MHz using external crystals**, which matters because USART timing depends on clock setup.
- The entire circuit is intended for **Proteus simulation**, not a general-purpose runtime environment.
- The circuit project is the integration boundary that binds MCU firmware to physical-like peripherals in the simulator.
10. **Build and deployment artifacts**
- Each MCU has its own **Atmel Studio project**:
- `master.atsln` / `master.cproj`
- `slave.atsln` / `slave.cproj`
- The resulting **hex files** are loaded into the Proteus schematic, so the architecture is effectively:
- source code → compiled hex → simulated MCU instances
11. **Repo organization as architecture**
- The repository structure mirrors the system decomposition:
- `Codes/Master` = control logic and output driving
- `Codes/Slave` = serial receive and LCD presentation
- `Circuit Diagram` = wiring and integration
- That separation is important for drawing the architecture diagram accurately: this is a **two-firmware, one-circuit** system with a **serial interface between independent MCUs**.
Main entry points: [`Master-Slave Dice Roller System/Circuit Diagram/Proteus_Circuit.pdsprj`](https://github.com/shimanto008/master-slave-dice-roller/blob/HEAD/Master-Slave%20Dice%20Roller%20System/Circuit%20Diagram/Proteus_Circuit.pdsprj) (Proteus Schematic), [`Master-Slave Dice Roller System`](https://github.com/shimanto008/master-slave-dice-roller/tree/HEAD/Master-Slave%20Dice%20Roller%20System) (Dice System), [`Master-Slave Dice Roller System/Codes/Master`](https://github.com/shimanto008/master-slave-dice-roller/tree/HEAD/Master-Slave%20Dice%20Roller%20System/Codes/Master) (Master Firmware), [`Master-Slave Dice Roller System/Codes/Master/main.c`](https://github.com/shimanto008/master-slave-dice-roller/blob/HEAD/Master-Slave%20Dice%20Roller%20System/Codes/Master/main.c) (Game Logic)
## Diagram (Mermaid)
```mermaid
flowchart TD
subgraph group_codes["Codes"]
node_master_fw["Master Firmware"]
node_master_src["Game Logic
c source
[main.c]"]
node_master_hex["Master HEX
deploy artifact
[master.hex]"]
node_slave_fw["Slave Firmware"]
node_slave_src["LCD Logic
c source
[main.c]"]
node_slave_hex["Slave HEX
deploy artifact
[slave.hex]"]
end
subgraph group_circuit["Circuit"]
node_button(("Roll Button
input"))
node_master_out["Master Outputs
display/leds"]
node_serial["USART Link
serial line"]
node_lcd["16x2 LCD
display"]
node_circuit_proj["Proteus Schematic
simulation project"]
end
node_repo{{"Dice System
embedded sim"}}
node_master_mcu(("Master ATmega32
runtime mcu"))
node_packet["USART Frame
5-byte protocol"]
node_slave_mcu(("Slave ATmega32
runtime mcu"))
node_repo -->|"contains"| node_master_fw
node_repo -->|"contains"| node_slave_fw
node_repo -->|"contains"| node_circuit_proj
node_master_fw -->|"implements"| node_master_src
node_master_src -->|"builds to"| node_master_hex
node_master_hex -->|"loads into"| node_master_mcu
node_button -->|"triggers"| node_master_mcu
node_master_mcu -->|"drives"| node_master_out
node_master_mcu -->|"encodes"| node_packet
node_packet -->|"transmits over"| node_serial
node_serial -->|"receives"| node_slave_mcu
node_slave_fw -->|"implements"| node_slave_src
node_slave_src -->|"builds to"| node_slave_hex
node_slave_hex -->|"loads into"| node_slave_mcu
node_slave_mcu -->|"renders to"| node_lcd
node_circuit_proj -->|"instantiates"| node_master_mcu
node_circuit_proj -->|"instantiates"| node_slave_mcu
node_circuit_proj -->|"wires"| node_serial
click node_repo "https://github.com/shimanto008/master-slave-dice-roller/tree/main/Master-Slave Dice Roller System"
click node_master_fw "https://github.com/shimanto008/master-slave-dice-roller/tree/main/Master-Slave Dice Roller System/Codes/Master"
click node_master_src "https://github.com/shimanto008/master-slave-dice-roller/blob/main/Master-Slave Dice Roller System/Codes/Master/main.c"
click node_master_hex "https://github.com/shimanto008/master-slave-dice-roller/blob/main/Master-Slave Dice Roller System/Codes/Master/master.hex"
click node_slave_fw "https://github.com/shimanto008/master-slave-dice-roller/tree/main/Master-Slave Dice Roller System/Codes/Slave"
click node_slave_src "https://github.com/shimanto008/master-slave-dice-roller/blob/main/Master-Slave Dice Roller System/Codes/Slave/main.c"
click node_slave_hex "https://github.com/shimanto008/master-slave-dice-roller/blob/main/Master-Slave Dice Roller System/Codes/Slave/slave.hex"
click node_circuit_proj "https://github.com/shimanto008/master-slave-dice-roller/blob/main/Master-Slave Dice Roller System/Circuit Diagram/Proteus_Circuit.pdsprj"
classDef toneNeutral fill:#f8fafc,stroke:#334155,stroke-width:1.5px,color:#0f172a
classDef toneBlue fill:#dbeafe,stroke:#2563eb,stroke-width:1.5px,color:#172554
classDef toneAmber fill:#fef3c7,stroke:#d97706,stroke-width:1.5px,color:#78350f
classDef toneMint fill:#dcfce7,stroke:#16a34a,stroke-width:1.5px,color:#14532d
classDef toneRose fill:#ffe4e6,stroke:#e11d48,stroke-width:1.5px,color:#881337
classDef toneIndigo fill:#e0e7ff,stroke:#4f46e5,stroke-width:1.5px,color:#312e81
classDef toneTeal fill:#ccfbf1,stroke:#0f766e,stroke-width:1.5px,color:#134e4a
class node_master_fw,node_master_src,node_master_hex,node_slave_fw,node_slave_src,node_slave_hex toneBlue
class node_button,node_master_out,node_serial,node_lcd,node_circuit_proj toneAmber
class node_repo,node_master_mcu,node_packet,node_slave_mcu toneNeutral
```
## Components
### Codes
Firmware sources and build artifacts for the two ATmega32 nodes.
- [Master Firmware](https://github.com/shimanto008/master-slave-dice-roller/tree/HEAD/Master-Slave%20Dice%20Roller%20System/Codes/Master): firmware · Control-plane firmware for dice logic, local outputs, and USART framing. · `Master-Slave Dice Roller System/Codes/Master`
- [Game Logic](https://github.com/shimanto008/master-slave-dice-roller/blob/HEAD/Master-Slave%20Dice%20Roller%20System/Codes/Master/main.c): c source · Implements dice rolls, turn rules, LEDs, and serial packet creation. · `Master-Slave Dice Roller System/Codes/Master/main.c`
- [Master HEX](https://github.com/shimanto008/master-slave-dice-roller/blob/HEAD/Master-Slave%20Dice%20Roller%20System/Codes/Master/master.hex): deploy artifact · Compiled image loaded into the Proteus master MCU instance. · `Master-Slave Dice Roller System/Codes/Master/master.hex`
- [Slave Firmware](https://github.com/shimanto008/master-slave-dice-roller/tree/HEAD/Master-Slave%20Dice%20Roller%20System/Codes/Slave): firmware · Display-plane firmware that receives frames and formats LCD history. · `Master-Slave Dice Roller System/Codes/Slave`
- [LCD Logic](https://github.com/shimanto008/master-slave-dice-roller/blob/HEAD/Master-Slave%20Dice%20Roller%20System/Codes/Slave/main.c): c source · Parses serial data and updates turn history and status messages. · `Master-Slave Dice Roller System/Codes/Slave/main.c`
- [Slave HEX](https://github.com/shimanto008/master-slave-dice-roller/blob/HEAD/Master-Slave%20Dice%20Roller%20System/Codes/Slave/slave.hex): deploy artifact · Compiled image loaded into the Proteus slave MCU instance. · `Master-Slave Dice Roller System/Codes/Slave/slave.hex`
### Circuit
Proteus schematic that integrates both MCUs and peripherals.
- **Roll Button**: input · User push button on PD2/INT0 that triggers a dice roll.
- **Master Outputs**: display/leds · 7-segment dice value on PORTC and three status LEDs on PB0-PB2.
- **USART Link**: serial line · One-way master TX to slave RX communication boundary.
- **16x2 LCD**: display · HD44780-compatible character LCD for roll history and status messages.
- [Proteus Schematic](https://github.com/shimanto008/master-slave-dice-roller/blob/HEAD/Master-Slave%20Dice%20Roller%20System/Circuit%20Diagram/Proteus_Circuit.pdsprj): simulation project · Integrates both MCUs, crystals, serial wiring, button, LEDs, 7-segment display, and LCD. · `Master-Slave Dice Roller System/Circuit Diagram/Proteus_Circuit.pdsprj`
### Other components
- [Dice System](https://github.com/shimanto008/master-slave-dice-roller/tree/HEAD/Master-Slave%20Dice%20Roller%20System): embedded sim · Two-node master/slave dice roller built for Proteus simulation. · `Master-Slave Dice Roller System`
- **Master ATmega32**: runtime mcu · Executes roll control, drives the 7-segment display and status LEDs.
- **USART Frame**: 5-byte protocol · Master-to-slave packet with start byte, dice value, player ID, status, and end byte.
- **Slave ATmega32**: runtime mcu · Receives USART data and renders history on the LCD.
## Connections
- Dice System → Master Firmware: contains · Repository groups the master firmware subsystem.
- Dice System → Slave Firmware: contains · Repository groups the slave firmware subsystem.
- Dice System → Proteus Schematic: contains · Repository includes the Proteus integration schematic.
- Master Firmware → Game Logic: implements · Master source defines the game control logic.
- Game Logic → Master HEX: builds to · Atmel Studio project compiles into the deployable HEX image.
- Master HEX → Master ATmega32: loads into · Proteus runs the compiled master image on the simulated MCU.
- Roll Button → Master ATmega32: triggers · Push button on INT0 initiates a roll on the master side.
- Master ATmega32 → Master Outputs: drives · Master updates the dice display and status LEDs immediately.
- Master ATmega32 → USART Frame: encodes · Roll result and status are packaged into the framed USART message.
- USART Frame → USART Link: transmits over · Framed bytes move one-way from master TX to slave RX.
- USART Link → Slave ATmega32: receives · Slave ATmega32 listens on RXD for master updates.
- Slave Firmware → LCD Logic: implements · Slave source defines serial parsing and LCD presentation.
- LCD Logic → Slave HEX: builds to · Atmel Studio project compiles into the deployable HEX image.
- Slave HEX → Slave ATmega32: loads into · Proteus runs the compiled slave image on the simulated MCU.
- Slave ATmega32 → 16x2 LCD: renders to · Slave presents roll history and status text on the LCD.
- Proteus Schematic → Master ATmega32: instantiates · Proteus schematic hosts the master MCU and its peripherals.
- Proteus Schematic → Slave ATmega32: instantiates · Proteus schematic hosts the slave MCU and its peripherals.
- Proteus Schematic → USART Link: wires · Schematic connects the USART boundary between both MCUs.