SenseCAP Indicator D1 Pro — Dashboard Firmware

PlatformIO firmware for the Seeed SenseCAP Indicator D1 Pro (ESP32-S3 + 4" RGB touchscreen).

The device connects to WiFi, polls a local display server, and renders a fully customizable XML-driven dashboard with swipeable pages.

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Architecture Overview

┌─────────────────────────────────────────────────────┐
│  Mac (display server)         SenseCAP Indicator    │
│                                                     │
│  display_server.py  ──HTTP──▶  firmware (ESP32-S3) │
│   /layout.xml                   XML parser          │
│   /data.json                    widget factory      │
│   /health                       placeholder engine  │
│                                 LVGL renderer       │
└─────────────────────────────────────────────────────┘

• Layout (/layout.xml) — defines the UI structure; cached by firmware until X-Layout-Version header changes
• Data (/data.json) — dynamic values (weather, news, crypto…); refreshed on swipe-down
• Pull-to-refresh — swipe down on any page to reload data; if layout version changed, full UI reload

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Project Structure

sensecap-d1-display/
├── platformio.ini
├── include/
│   ├── config.h                # WiFi, server host/port, timeouts
│   └── lv_conf.h               # LVGL configuration
├── src/
│   ├── main.cpp                # Entry point, FreeRTOS tasks
│   ├── xml_parser.cpp          # XML layout parser
│   ├── widget_factory.cpp      # LVGL widget builder from XML
│   ├── placeholder_engine.cpp  # {placeholder} substitution + live updates
│   ├── data_fetcher.cpp        # HTTP fetch + JSON parse
│   ├── screen_manager.cpp      # Swipeable pages
│   ├── ui.cpp                  # Top-level UI init
│   ├── grove_sensor.cpp        # SGP40 (tVOC) + SCD41 (CO2) via I2C
│   ├── settings_manager.cpp
│   └── fonts/                  # Merged Montserrat + NotoSansSymbols2
├── scripts/
│   └── setup_lvgl.py           # Pre-build: patches LVGL include path
└── server/
    ├── display_server.py       # Python HTTP server (port 8765)
    └── server.log

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Hardware

Component	Specs
Main MCU	ESP32-S3 (240 MHz, WiFi + BT, 8MB flash, 8MB PSRAM OPI)
Secondary MCU	RP2040
Display	4" ST7701S RGB 480×480
Touch	FT5X06 capacitive
I2C expander	PCA9535 at 0x20 (SDA=39, SCL=40)
Sensors	SGP40 (tVOC), SCD41 (CO2)

USB Ports

Port	Purpose
/dev/cu.wchusbserial2110	ESP32-S3 (flash/log)
/dev/cu.usbmodem21201	RP2040

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Build & Flash

Flash firmware (C++ changes only)

cd ~/Source/GitHub/simonerom/sensecap-d1-display
python3 -m platformio run -e sensecap_indicator --target upload --upload-port /dev/cu.wchusbserial2110

Serial monitor

python3 -m platformio device monitor --port /dev/cu.usbmodem21201 --baud 115200

When to flash vs swipe down

Changed file	Action needed
src/*.cpp / include/*.h	Flash
server/display_server.py	Restart server + swipe down
Layout XML (inside server)	Bump SPEC_VERSION + restart server + swipe down

Never flash for server or layout changes — swipe down is enough.

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Display Server

The server runs on the Mac and serves layout + data to the device.

Start / Stop

# Restart after editing display_server.py
launchctl unload ~/Library/LaunchAgents/com.simonerom.sensecap-server.plist
launchctl load ~/Library/LaunchAgents/com.simonerom.sensecap-server.plist

Endpoints

Endpoint	Description
GET /layout.xml	XML UI layout (cached by device)
GET /data.json	Dynamic data (refreshed on swipe)
GET /health	{"status":"ok","version":"..."}

Server: http://192.168.1.29:8765/

Applying layout changes

1. Edit the XML layout inside display_server.py
2. Bump SPEC_VERSION (e.g. "1.3.6" → "1.3.7") and the <screens version="..."> attribute
3. Restart the server
4. Swipe down on the device

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XML Layout

Pages are defined in display_server.py inside the LAYOUT_XML string.

Elements

Element	Description
<screens>	Root container, version attribute
<screen>	One swipeable page, bg color
<card>	Rounded container: bg, radius, pad, pad_h, pad_v, gap, tight, flex, h, scroll, valign
<row>	Horizontal flex container: gap, h
<col>	Vertical flex container: gap, flex
<label>	Text label: text, font, bold, color, align, max_lines, flex, w, visible
<list>	Bulleted list from array placeholder: items, font, color, divider, max_lines
<crypto_row>	Coin row: symbol, price, change, trend, up_color, down_color

Placeholders

Any {key} in a text attribute is replaced live from data.json.
Arrays ({news_italia}, {scioperi}, etc.) are used with <list items="{key}"/>.

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data.json Reference

Field	Type	Description
indoor_temp	string	Indoor temperature (SHT40)
indoor_hum	string	Indoor humidity
outdoor_temp	string	Outdoor temperature (Open-Meteo)
voc	string	tVOC index (SGP40) or --
co2	string	CO2 ppm (SCD41) or --
day_name	string	Weekday in Italian uppercase (e.g. LUNEDI)
day_num	string	Day of month
month_name	string	Full Italian month name (e.g. Marzo)
day_color	string	#E53935 on Sunday/holidays, dark otherwise
meteo_summary	string	Multi-line weather + forecast + rain info
scioperi	array	Upcoming ATM/transit strikes
scioperi_text	string	Same, newline-joined (for single label)
scioperi_visible	string	"true" / "false"
news_italia	array	Italian news (ANSA)
news_estero	array	International news (Google News IT)
news_milano	array	Milan local news
btc_price/change/trend	string	Bitcoin
eth_price/change/trend	string	Ethereum
iotx_price/change/trend	string	IoTeX
curiosity	string	Daily curiosity fact

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Fonts

Merged Montserrat + NotoSansSymbols2, compiled in src/fonts/.

Function	Description
lv_hlp_font(size)	Regular (sizes: 12,14,18,22,24,28,32,48,64,96)
lv_hlp_font_bold(size)	Bold (sizes: 18,24,28,32,96,192)
lv_hlp_font_ex(size, bold)	Auto-selects variant

Font 192 bold contains digits only (used for large day-of-month number).
Supported symbols: ★ ▲ ▶ ◆ ◉ ☀ ☁ ⚠ ⚡ ° •

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Dependencies

Library	Version
lvgl/lvgl	^8.3.11
bblanchon/ArduinoJson	^7.0.4
Arduino_GFX	(RGB display driver)

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License

MIT