Replace USB serial/HID with Bluetooth Low Energy

Move all communication from USB to BLE. The device now advertises as
"Claude Controller" and acts as both a BLE HID keyboard (for touch
gestures) and a GATT data server (for usage updates from the daemon).

- Add NimBLE-Arduino BLE module with custom GATT service + HID keyboard
- Add third screen (Bluetooth) with connection status, MAC, reset button
- Rewrite daemon in bash using bluetoothctl/busctl for BLE GATT writes
- Add screenshot capture via LVGL snapshot over serial
- Remove TinyUSB mode — normal pio upload works again
- Update README with BLE architecture, screenshots, gesture docs

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
Hermann Björgvin Haraldsson
2026-04-04 19:30:19 +00:00
co-authored by Claude Opus 4.6
parent 930055170f
commit 10b8052bcc
22 changed files with 917 additions and 167 deletions
+144 -46
View File
@@ -1,14 +1,16 @@
#!/bin/bash
# Claude Usage Tracker Daemon
# Reads Claude Code OAuth token, polls usage via API, sends to ESP32 over serial.
# Survives USB plug/unplug cycles using inotifywait for instant device detection.
# Dependencies: curl, awk, inotify-tools
# Claude Usage Tracker Daemon (BLE)
# Reads Claude Code OAuth token, polls usage via API, sends to ESP32 over BLE GATT.
# Auto-connects and reconnects to the Claude Controller BLE device.
# Dependencies: curl, awk, bluetoothctl
SERIAL_PORT="${SERIAL_PORT:-/dev/ttyACM0}"
SERIAL_DEV=$(basename "$SERIAL_PORT")
DEVICE_NAME="Claude Controller"
DEVICE_MAC="${DEVICE_MAC:-}" # auto-discovered if empty
SERVICE_UUID="4c41555a-4465-7669-6365-000000000001"
RX_CHAR_UUID="4c41555a-4465-7669-6365-000000000002"
POLL_INTERVAL=30
BAUD=115200
SERIAL_FD=3
SAVED_MAC_FILE="$HOME/.config/claude-usage-monitor/ble-address"
DBUS_DEST="org.bluez"
log() {
echo "[$(date '+%H:%M:%S')] $1"
@@ -18,27 +20,112 @@ read_token() {
grep -o '"accessToken":"[^"]*"' "$HOME/.claude/.credentials.json" | cut -d'"' -f4
}
device_connected() {
[ -e "$SERIAL_PORT" ]
# Convert MAC to D-Bus path: AA:BB:CC:DD:EE:FF -> dev_AA_BB_CC_DD_EE_FF
mac_to_dbus_path() {
local adapter
adapter=$(busctl call org.bluez / org.freedesktop.DBus.ObjectManager GetManagedObjects 2>/dev/null | grep -o '/org/bluez/hci[0-9]' | head -1)
adapter=${adapter:-/org/bluez/hci0}
echo "${adapter}/dev_$(echo "$1" | tr ':' '_')"
}
open_serial() {
stty -F "$SERIAL_PORT" "$BAUD" raw -echo -echoe -echok 2>/dev/null || return 1
eval "exec ${SERIAL_FD}<>\"$SERIAL_PORT\"" 2>/dev/null || return 1
return 0
# Check if device is connected via D-Bus
is_connected() {
local path
path=$(mac_to_dbus_path "$DEVICE_MAC")
busctl get-property "$DBUS_DEST" "$path" org.bluez.Device1 Connected 2>/dev/null | grep -q "true"
}
close_serial() {
eval "exec ${SERIAL_FD}>&-" 2>/dev/null
# Load saved MAC address
load_mac() {
if [ -n "$DEVICE_MAC" ]; then return 0; fi
if [ -f "$SAVED_MAC_FILE" ]; then
DEVICE_MAC=$(cat "$SAVED_MAC_FILE")
[ -n "$DEVICE_MAC" ] && return 0
fi
return 1
}
# Wait for device to appear using inotifywait (blocks, zero CPU)
wait_for_device() {
while ! device_connected; do
inotifywait -qq -e create /dev --include "$SERIAL_DEV" 2>/dev/null || sleep 1
# Save MAC for fast reconnect
save_mac() {
mkdir -p "$(dirname "$SAVED_MAC_FILE")"
echo "$DEVICE_MAC" > "$SAVED_MAC_FILE"
}
# Scan for Claude Controller
scan_for_device() {
log "Scanning for '$DEVICE_NAME'..."
# Start LE scan
bluetoothctl scan le &>/dev/null &
local scan_pid=$!
sleep 8
kill "$scan_pid" 2>/dev/null
wait "$scan_pid" 2>/dev/null
# Find the device
local found
found=$(bluetoothctl devices 2>/dev/null | grep "$DEVICE_NAME" | awk '{print $2}')
if [ -n "$found" ]; then
DEVICE_MAC="$found"
save_mac
log "Found: $DEVICE_MAC"
return 0
fi
return 1
}
# Connect to the device
connect_device() {
log "Connecting to $DEVICE_MAC..."
# Trust first (allows auto-reconnect)
bluetoothctl trust "$DEVICE_MAC" &>/dev/null
# Connect
bluetoothctl connect "$DEVICE_MAC" &>/dev/null
sleep 2
if is_connected; then
log "Connected"
return 0
fi
log "Connection failed"
return 1
}
# Find the GATT characteristic handle via D-Bus
find_rx_char_path() {
local dev_path
dev_path=$(mac_to_dbus_path "$DEVICE_MAC")
# Search for our RX characteristic UUID in the device's GATT tree
busctl tree "$DBUS_DEST" 2>/dev/null | grep -o "${dev_path}/service[0-9a-f]*/char[0-9a-f]*" | while read -r char_path; do
local uuid
uuid=$(busctl get-property "$DBUS_DEST" "$char_path" org.bluez.GattCharacteristic1 UUID 2>/dev/null | tr -d '"' | awk '{print $2}')
if [ "$uuid" = "$RX_CHAR_UUID" ]; then
echo "$char_path"
return 0
fi
done
}
# Write data to the RX characteristic via D-Bus
write_gatt() {
local char_path="$1"
local data="$2"
# Convert string to byte array for D-Bus: "hi" -> 0x68 0x69
local bytes=""
for ((i = 0; i < ${#data}; i++)); do
local byte
byte=$(printf "0x%02x" "'${data:$i:1}")
bytes="$bytes $byte"
done
local count=${#data}
busctl call "$DBUS_DEST" "$char_path" org.bluez.GattCharacteristic1 \
WriteValue "aya{sv}" "$count" $bytes 0 2>/dev/null
}
poll() {
local token
token=$(read_token) || { log "Error: could not read token"; return 1; }
@@ -69,7 +156,6 @@ poll() {
s7d_reset=${s7d_reset:-0}
status=${status:-unknown}
# Build JSON payload in a single awk process (utilization * 100, timestamps to minutes)
local payload
payload=$(awk -v u5="$s5h_util" -v r5="$s5h_reset" -v u7="$s7d_util" -v r7="$s7d_reset" -v st="$status" -v now="$now" \
'BEGIN {
@@ -80,49 +166,61 @@ poll() {
printf "{\"s\":%s,\"sr\":%s,\"w\":%s,\"wr\":%s,\"st\":\"%s\",\"ok\":true}", sp, sr, wp, wr, st;
}')
if ! echo "$payload" >&${SERIAL_FD} 2>/dev/null; then
log "Write failed - device disconnected"
return 1
fi
log "Sending: $payload"
write_gatt "$RX_CHAR_PATH" "$payload" || { log "Write failed"; return 1; }
return 0
}
cleanup() {
close_serial
log "Daemon stopped"
exit 0
}
trap cleanup INT TERM
log "=== Claude Usage Tracker Daemon ==="
log "Serial port: $SERIAL_PORT"
log "=== Claude Usage Tracker Daemon (BLE) ==="
log "Poll interval: ${POLL_INTERVAL}s"
BACKOFF=1
while true; do
# Wait for device (instant detection via inotify, or already plugged in)
if ! device_connected; then
log "Waiting for device..."
wait_for_device
# Find the device
if ! load_mac; then
scan_for_device || {
log "Device not found, retrying in ${BACKOFF}s..."
sleep "$BACKOFF"
BACKOFF=$((BACKOFF < 60 ? BACKOFF * 2 : 60))
continue
}
fi
log "Device connected"
sleep 2 # wait for ESP32 boot
# Connect if not connected
if ! is_connected; then
connect_device || {
log "Retrying in ${BACKOFF}s..."
sleep "$BACKOFF"
BACKOFF=$((BACKOFF < 60 ? BACKOFF * 2 : 60))
continue
}
fi
if ! open_serial; then
log "Failed to open serial port"
sleep 2
# Find the GATT characteristic
RX_CHAR_PATH=$(find_rx_char_path)
if [ -z "$RX_CHAR_PATH" ]; then
log "Error: RX characteristic not found, retrying..."
sleep 5
continue
fi
log "Serial port opened"
log "GATT RX path: $RX_CHAR_PATH"
# Poll loop - polls API every POLL_INTERVAL, exits on disconnect or write failure
while device_connected; do
poll || break
# Sleep POLL_INTERVAL but wake instantly if device disappears
inotifywait -qq -e delete /dev --include "$SERIAL_DEV" -t "$POLL_INTERVAL" 2>/dev/null
BACKOFF=1 # reset backoff on successful connection
# Poll loop
while is_connected; do
poll || log "Poll failed, will retry"
sleep "$POLL_INTERVAL"
done
# Disconnected - clean up and loop back to wait
log "Device disconnected"
close_serial
log "Device disconnected, reconnecting..."
sleep 2
done