5a05ee99a1
- ESP32-C3 SPI slave project with ESP-NOW broadcast functionality - Raspberry Pi SPI master test tools and CLI for JSON communication - Merged src/ directory from full branch with lighting controller code - Updated Pipfile with system install scripts and ESP32 monitoring - Added comprehensive test suite for SPI communication
74 lines
1.8 KiB
Markdown
74 lines
1.8 KiB
Markdown
# ESP32-C3 SPI Slave with ESP-NOW Project
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This ESP-IDF project implements an SPI slave device that broadcasts received data via ESP-NOW with the following GPIO configuration:
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- **MOSI**: GPIO10
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- **MISO**: GPIO9
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- **SCLK**: GPIO20
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- **CS**: GPIO7
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## Features
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- SPI Mode 0 (CPOL=0, CPHA=0)
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- 256-byte buffer for data exchange
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- DMA support for efficient transfers
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- Real-time data logging via UART
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- **ESP-NOW broadcasting** of received SPI data
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- Timestamped data packets
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- Broadcast to all nearby ESP32 devices
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## Building and Flashing
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1. Set up ESP-IDF environment:
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```bash
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. $HOME/esp/esp-idf/export.sh
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```
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2. Build the project:
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```bash
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cd esp32
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idf.py build
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```
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3. Flash to ESP32-C3:
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```bash
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idf.py -p /dev/ttyUSB0 flash monitor
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```
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## Usage
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The ESP32-C3 will act as an SPI slave device, waiting for transactions from an SPI master. When data is received, it will:
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1. Print the received data to the serial console
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2. **Broadcast the received data via ESP-NOW** to all nearby ESP32-C3 devices
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3. Send back a test pattern (0x00, 0x01, 0x02, ...)
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4. Wait for the next transaction
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## ESP-NOW Data Format
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The broadcasted data includes:
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- **Data**: The actual SPI received data (up to 256 bytes)
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- **Length**: Number of bytes received
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- **Timestamp**: Millisecond timestamp when data was received
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## Receiving ESP-NOW Data
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To receive the broadcasted data on another ESP32-C3 device, you can use the ESP-NOW receive callback function. The data structure is:
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```c
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typedef struct {
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uint8_t data[256]; // Received SPI data
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uint8_t length; // Number of bytes
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uint32_t timestamp; // Timestamp in milliseconds
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} espnow_data_t;
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```
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## Serial Monitor
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Connect to the serial monitor to see debug output:
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```bash
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idf.py -p /dev/ttyUSB0 monitor
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```
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The device will log received SPI data and transaction status.
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