File System

The RoArm-M2-S uses the ESP32’s SPIFFS (SPI Flash File System) to store configuration files, mission sequences, and WiFi credentials. You can manage these files through JSON commands.

Scanning Files

List all files stored in flash:

{"T":200}

Returns a list of filenames with their sizes.

Creating Files

Create a new file with initial content:

{"T":201,"name":"config.txt","content":"initial content here"}

Reading Files

Read the entire contents of a file:

{"T":202,"name":"config.txt"}

Read a single line by line number:

{"T":207,"name":"config.txt","lineNum":3}

Modifying Files

Append a Line

Add content to the end of a file:

{"T":204,"name":"config.txt","content":"new line at end"}

Insert a Line

Insert a new line at a specific position:

{"T":205,"name":"config.txt","lineNum":3,"content":"inserted content"}

Replace a Line

Overwrite a specific line:

{"T":206,"name":"config.txt","lineNum":3,"content":"replacement content"}

Delete a Line

Remove a specific line:

{"T":208,"name":"config.txt","lineNum":3}

Deleting Files

Remove a file from flash:

{"T":203,"name":"config.txt"}

Flash Space

Check available storage:

{"T":601}

Caution

SPIFFS has limited space (typically ~1.5MB on a 4MB flash). Mission files with many steps can consume significant space. Monitor usage with T:601 periodically.

System Files

The firmware uses these files internally:

Filename	Purpose
wifiConfig.json	WiFi mode, SSID, and password
Mission files	Named by user (e.g., pick_place)

Danger

Deleting wifiConfig.json will reset WiFi to default AP mode on next boot. This can be useful for recovery but will lose your network configuration.

Command Summary

T-Code	Command	Description
200	Scan files	List all files and sizes
201	Create file	New file with content
202	Read file	Full file contents
203	Delete file	Remove file
204	Append line	Add to end of file
205	Insert line	Insert at line number
206	Replace line	Overwrite at line number
207	Read line	Read single line
208	Delete line	Remove single line
601	Free space	Check available flash

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File system reference from firmware source json_cmd.h.