Replace synchronous WebServer with ESPAsyncWebServer:
- Fully callback-based, no polling loop needed
- Handles HTTP parsing asynchronously in background
- Larger chunk sizes from async TCP handling
- Known to achieve 500KB-1MB/s vs 200KB/s with sync WebServer
Key changes:
- platformio.ini: Add ESP Async WebServer dependency
- CrossPointWebServer: Rewrite for async API
- CrossPointWebServerActivity: Remove handleClient loop
The sync WebServer was capped at ~200KB/s due to its
synchronous design and small chunk sizes.
Major architectural changes:
- Remove complex 64KB circular buffer (was adding overhead)
- Use simple direct SD writes (ESP32 WebServer already buffers)
- Add detailed timing diagnostics (write count, avg write time, % time in writes)
WiFi optimizations enhanced:
- Explicit WIFI_PS_NONE power save disable
- Force 802.11b/g/n protocol for better throughput
- Log actual TX power and RSSI for debugging
The circular buffer was copying data twice (WiFi→buffer→SD) and adding
complexity. Direct writes let the WebServer's internal buffering work
optimally. Diagnostics will help identify if SD card speed is the bottleneck.
- Replace byte-by-byte copies with memcpy (10-100x faster)
- Increase SD write chunk size from 4KB to 16KB
- Use static buffer for SD writes to reduce stack usage
- Remove unnecessary yield() from handleClient loop
The byte-by-byte circular buffer operations were a major bottleneck.
Using memcpy with proper wrap-around handling significantly improves
throughput.
## Summary
Adds support for browsing and downloading books from a Calibre-web
server via OPDS.
How it works
1. Configure server URL in Settings → Calibre Web URL (e.g.,
https://myserver.com:port I use Cloudflare tunnel to make my server
accessible anywhere fwiw)
2. "Calibre Library" will now show on the the home screen
3. Browse the catalog - navigate through categories like "By Newest",
"By Author", "By Series", etc.
4. Download books - select a book and press Confirm to download the EPUB
to your device
Navigation
- Up/Down - Move through entries
- Confirm - Open folder or download book
- Back - Go to parent catalog, or exit to home if at root
- Navigation entries show with > prefix, books show title and author
- Button hints update dynamically ("Open" for folders, "Download" for
books)
Technical details
- Fetches OPDS catalog from {server_url}/opds
- Parses both navigation feeds (catalog links) and acquisition feeds
(downloadable books)
- Maintains navigation history stack for back navigation
- Handles absolute paths in OPDS links correctly (e.g.,
/books/opds/navcatalog/...)
- Downloads EPUBs directly to the SD card root
Note
The server URL should be typed to include https:// if the server
requires it - HTTP→HTTPS redirects may cause SSL errors on ESP32.
## Additional Context
* I also changed the home titles to use uppercase for each word and
added a setting to change the size of the side margins
---------
Co-authored-by: Dave Allie <dave@daveallie.com>
## Summary
* **What is the goal of this PR?** Fixes a bug -
https://github.com/daveallie/crosspoint-reader/issues/187 - where the
screen would freeze after entering a WiFi password, causing the device
to appear hung.
* **What changes are included?**
- Fixed a race condition in `WifiSelectionActivity::displayTaskLoop()`
that caused rendering of an empty screen when transitioning from the
keyboard subactivity
- Added `vTaskDelay()` when a subactivity is active to prevent CPU
starvation from a tight `continue` loop
- Added a check to skip rendering when in `PASSWORD_ENTRY` state,
allowing the state machine to properly transition to `CONNECTING` before
the display updates
## Additional Context
* **Root cause:** When the keyboard subactivity exited after password
entry, the display task would wake up and attempt to render. However,
the `state` was still `PASSWORD_ENTRY` (before `attemptConnection()`
changed it to `CONNECTING`), and since there was no render case for
`PASSWORD_ENTRY`, the display would show a cleared/empty buffer,
appearing frozen.
* **Performance implications:** The added `vTaskDelay(10)` calls when
subactivity is active or in `PASSWORD_ENTRY` state actually improve
performance by preventing CPU starvation - previously the display task
would spin in a tight loop with `continue` while a subactivity was
present.
* **Testing focus:** Test the full WiFi connection flow:
1. Enter network selection
2. Select a network requiring a password
3. Enter password and press OK
4. Verify "Connecting..." screen appears
5. Verify connection completes and prompts to save password
## Summary
* **What is the goal of this PR?** Fixes#199 - Device falls asleep
during WiFi file transfer after 10 minutes of inactivity, disconnecting
the web server.
* **What changes are included?**
- Add `preventAutoSleep()` virtual method to `Activity` base class
- Modify main loop to reset inactivity timer when `preventAutoSleep()`
returns true
- Override `preventAutoSleep()` in `CrossPointWebServerActivity`
(returns true when web server running)
- Override `preventAutoSleep()` in `OtaUpdateActivity` (returns true
during update check/download)
## Additional Context
* The existing `skipLoopDelay()` method controls loop timing (yield vs
delay) for HTTP responsiveness. The new `preventAutoSleep()` method is
semantically separate - it explicitly signals that an activity should
keep the device awake.
* `CrossPointWebServerActivity` uses both methods: `skipLoopDelay()` for
responsive HTTP handling, `preventAutoSleep()` for staying awake.
* `OtaUpdateActivity` only needs `preventAutoSleep()` since the OTA
library handles HTTP internally.
## Summary
* Update EpdFontFamily::Style to be u8 instead of u32 (saving 3 bytes
per word)
* Update layout width/height to be u16 from int
* Update page element count to be u16 from u32
* Update text block element count to be u16 from u32
* Bumped section bin version to version 8
## Summary
* Swap to updated SDCardManager which uses SdFat
* Add exFAT support
* Swap to using FsFile everywhere
* Use newly exposed `SdMan` macro to get to static instance of
SDCardManager
* Move a bunch of FsHelpers up to SDCardManager
## Summary
**What is the goal of this PR?**
Adds a setting to swap the front buttons. The default functionality are:
Back/Confirm/Left/Right. When this setting is enabled they become:
Left/Right/Back/Confirm. This makes it more comfortable to use when
holding in your right hand since your thumb can more easily rest on the
next button. The original firmware has a similar setting.
**What changes are included?**
- Add the new setting.
- Create a mapper to dynamically switch the buttons based on the
setting.
- Use mapper on the various activity screens.
- Update the button hints to reflect the swapped buttons.
## Additional Context
Full disclosure: I used Codex CLI to put this PR together, but did
review it to make sure it makes sense.
Also tested on my device:
https://share.cleanshot.com/k76891NY
## Summary
* Fix underscore on keyboard
* Remove special handling of special row characters
* Fix navigating between special row items
* Standardize keyboard activity to use standard loop
* Fix issue with rendering keyboard non-stop
Fixes https://github.com/daveallie/crosspoint-reader/issues/131
Using QRCode library from pio to generate the QR code.
Done:
- Display QR code for URL in network mode
- minor fixes of layout
- Display QR for URL in AP mode
- Display QR for AP in AP mode
---------
Co-authored-by: Dave Allie <dave@daveallie.com>
## Summary
This creates a `renderer.drawButtonHints` to make all of the "hints"
over buttons to match the home screen.
## Additional Context
* Add any other information that might be helpful for the reviewer
(e.g., performance implications, potential risks, specific areas to
focus on).
---------
Co-authored-by: Dave Allie <dave@daveallie.com>
## Summary
* **What is the goal of this PR?** Adds WiFi Access Point (AP) mode
support for File Transfer, allowing the device to create its own WiFi
network that users can connect to directly - useful when no existing
WiFi network is available. And in my experience is faster when the
device is right next to your laptop (but maybe further from your wifi)
* **What changes are included?**
- New `NetworkModeSelectionActivity` - an interstitial screen asking
users to choose between:
- "Join a Network" - connects to an existing WiFi network (existing
behavior)
- "Create Hotspot" - creates a WiFi access point named
"CrossPoint-Reader"
- Modified `CrossPointWebServerActivity` to:
- Launch the network mode selection screen before proceeding
- Support starting an Access Point with mDNS (`crosspoint.local`) and
DNS server for captive portal behavior
- Display appropriate connection info for both modes
- Modified `CrossPointWebServer` to support starting when WiFi is in AP
mode (not just STA connected mode)
## Additional Context
* **AP Mode Details**: The device creates an open WiFi network named
"CrossPoint-Reader". Once connected, users can access the file transfer
page at `http://crosspoint.local/` or `http://192.168.4.1/`
* **DNS Captive Portal**: A DNS server redirects all domain requests to
the device's IP, enabling captive portal behavior on some devices
* **mDNS**: Hostname resolution via `crosspoint.local` is enabled for
both AP and STA modes
* **No breaking changes**: The "Join a Network" option preserves the
existing WiFi connection flow
* **Memory impact**: Minimal - the AP mode uses roughly the same
resources as STA mode
## Summary
* Give activities name and log when entering and exiting them
* Clearer logs when attempting to debug, knowing where users are coming
from/going to helps
## Summary
- **What is the goal of this PR?**
Implements wireless EPUB file management via a built-in web server,
enabling users to upload, browse, organize, and delete EPUB files from
any device on the same WiFi network without needing a computer cable
connection.
- **What changes are included?**
- **New Web Server**
([`CrossPointWebServer.cpp`](src/CrossPointWebServer.cpp),
[`CrossPointWebServer.h`](src/CrossPointWebServer.h)):
- HTTP server on port 80 with a responsive HTML/CSS interface
- Home page showing device status (version, IP, free memory)
- File Manager with folder navigation and breadcrumb support
- EPUB file upload with progress tracking
- Folder creation and file/folder deletion
- XSS protection via HTML escaping
- Hidden system folders (`.` prefixed, "System Volume Information",
"XTCache")
- **WiFi Screen** ([`WifiScreen.cpp`](src/screens/WifiScreen.cpp),
[`WifiScreen.h`](src/screens/WifiScreen.h)):
- Network scanning with signal strength indicators
- Visual indicators for encrypted (`*`) and saved (`+`) networks
- State machine managing: scanning, network selection, password entry,
connecting, save/forget prompts
- 15-second connection timeout handling
- Integration with web server (starts on connect, stops on exit)
- **WiFi Credential Storage**
([`WifiCredentialStore.cpp`](src/WifiCredentialStore.cpp),
[`WifiCredentialStore.h`](src/WifiCredentialStore.h)):
- Persistent storage in `/sd/.crosspoint/wifi.bin`
- XOR obfuscation for stored passwords (basic protection against casual
reading)
- Up to 8 saved networks with add/remove/update operations
- **On-Screen Keyboard**
([`OnScreenKeyboard.cpp`](src/screens/OnScreenKeyboard.cpp),
[`OnScreenKeyboard.h`](src/screens/OnScreenKeyboard.h)):
- Reusable QWERTY keyboard component with shift support
- Special keys: Shift, Space, Backspace, Done
- Support for password masking mode
- **Settings Screen Integration**
([`SettingsScreen.h`](src/screens/SettingsScreen.h)):
- Added WiFi action to navigate to the new WiFi screen
- **Documentation** ([`docs/webserver.md`](docs/webserver.md)):
- Comprehensive user guide covering WiFi setup, web interface usage,
file management, troubleshooting, and security notes
- See this for more screenshots!
- Working "displays the right way in GitHub" on my repo:
https://github.com/olearycrew/crosspoint-reader/blob/feature/connect-to-wifi/docs/webserver.md
**Video demo**
https://github.com/user-attachments/assets/283e32dc-2d9f-4ae2-848e-01f41166a731
## Additional Context
- **Security considerations**: The web server has no
authentication—anyone on the same WiFi network can access files. This is
documented as a limitation, recommending use only on trusted private
networks. Password obfuscation in the credential store is XOR-based, not
cryptographically secure.
- **Memory implications**: The web server and WiFi stack consume
significant memory. The implementation properly cleans up (stops server,
disconnects WiFi, sets `WIFI_OFF` mode) when exiting the WiFi screen to
free resources.
- **Async operations**: Network scanning and connection use async
patterns with FreeRTOS tasks to prevent blocking the UI. The display
task handles rendering on a dedicated thread with mutex protection.
- **Browser compatibility**: The web interface uses standard
HTML5/CSS3/JavaScript and is tested to work with all modern browsers on
desktop and mobile.
---------
Co-authored-by: Dave Allie <dave@daveallie.com>
