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SolarOS 4.13.4 manual · api

Python bluetooth API

API overview · Lua bluetooth

solaros.ble

Top-level BLE functions expose keyboard pairing and layout controls. Generic characteristic I/O is separate, under solaros.ble.gatt.

Example:

import solaros

print(solaros.ble.status())
print("layout", solaros.ble.layout())

solaros.ble.hid

Available when BLE support is compiled. This typed peripheral API makes the SolarOS device advertise as one composite BLE keyboard, mouse, and gamepad. The OS owns the fixed HID-over-GATT report map, descriptors, encryption, bonding, and teardown; scripts cannot publish arbitrary HID descriptors or report bytes.

hid = solaros.ble.hid
hid.start("SolarOS Controls")
# Call only after an explicit user action to pair a new host.
hid.pair()

while not solaros.should_exit():
    event = hid.poll()
    if event is not None:
        print(event)
        if event["type"] == "passkey":
            print("Enter %06d on the remote host" % event["passkey"])
    if hid.status()["keyboard_subscribed"]:
        hid.keyboard.press(hid.KEY_LEFT_CTRL, hid.KEY_A)
        hid.keyboard.release_all()
        break

Input report operations require an encrypted host subscription for that report type and otherwise raise OSError("ESP_ERR_INVALID_STATE"). Keyboard LED bits are available as LED_NUM_LOCK, LED_CAPS_LOCK, LED_SCROLL_LOCK, LED_COMPOSE, and LED_KANA. Call poll() regularly and inspect events_dropped; the native queue holds 16 events and drops new events when full. The runtime owns this service and cleans it up on normal exit, uncaught exceptions, interruption, or forced stop.

solaros.ble.hid and solaros.ble.server share one connectable-advertising lease, so a runtime cannot use both simultaneously. Outgoing solaros.ble.gatt peers remain separate subject to the shared controller connection budget. This BLE API is independent of the dormant USB-only solaros.hid package described in Python input.

solaros.ble.scan()

Available when BLE support is compiled. Returns a list of up to 32 device dictionaries, including non-keyboard devices. Each record contains address (colon-separated hex), name (possibly empty), integer addr_type, rssi (dBm), appearance, and booleans hid_service, keyboard_like, remembered, and connected. Address types are 0 public, 1 random, 2 public identity, and 3 random identity.

Uses the same blocking scan as shell ble scan, with no arguments. Scan errors raise OSError; no devices returns an empty list. Scanning is rejected during sleep preparation or while a generic GATT link is active or retiring. Scan before connecting. Script cancellation is checked before and after the blocking service call; it does not interrupt the radio scan.

for device in solaros.ble.scan():
    print(device["address"], device["addr_type"], device["name"], device["rssi"])

solaros.ble.gatt

Available when BLE support is compiled. This synchronous client owns one session per Python runtime; Lua and the shell have separate owners. Each runtime may own multiple peers, with independent operations and connection state.

Arguments are positional. Timeouts accept 0..60000 milliseconds; zero selects 12 seconds for connect or 5 seconds for read/write/subscribe/unsubscribe. Errors raise OSError; cancellation reports BLE operation cancelled. Capacity exhaustion reports BLE connection capacity exhausted; allocation can also fail. Existing peers remain connected when another connection cannot be admitted. Connect peers sequentially: concurrent connection establishment can report ESP_ERR_INVALID_STATE. Timeout or cancellation retires only the affected connection. Release its peer handle and connect again after teardown finishes. Rediscover characteristic handles after every reconnect, including after sleep.

The runtime closes its session and all peers on normal exit, uncaught exceptions, and stop. Waiting operations check script stop/deadline state every 50 ms. In the REPL, the session lasts until the interpreter exits; use disconnect(peer) when done. An explicitly caught error does not end the runtime or release its session.

The current service retains at most 24 services and 64 characteristics per service. Reads return at most the first 128 bytes; writes accept 1..128 bytes and must fit within the negotiated MTU minus three bytes. mtu reports the negotiated value; connection setup performs MTU exchange before discovery. Notification queues preserve arrival order. Full queues drop new events; payloads exceeding 128 bytes are dropped whole, never truncated. Both increment the saturating events_dropped counter. NimBLE confirms indications at the protocol layer; confirmation does not mean the application consumed the event. Poll and monitor loss counters regularly. Disconnect, cancellation, timeout and sleep release queue storage and discard queued events. Loss counters remain readable for the peer handle's lifetime. Reconnect and resubscribe after sleep. No user callback runs on the Bluetooth task. There is no script MTU setter or automatic write chunking. Application services and advertising use 2, independently of these client peers.

import solaros

gatt = solaros.ble.gatt
peers = []
try:
    # Replace both addresses and address types with your peripherals.
    peers.append(gatt.connect("aa:bb:cc:dd:ee:01", 1))
    peers.append(gatt.connect("aa:bb:cc:dd:ee:02", 1))
    for peer in peers:
        print(gatt.status(peer))
        for service in gatt.services(peer):
            print(service)
            print(gatt.characteristics(peer, service["index"]))
        # Use a readable handle from this peer: print(gatt.read(peer, handle))
finally:
    for peer in peers:
        gatt.disconnect(peer)

For an already connected peer and a discovered notification-capable handle:

gatt.configure_queue(peer, 32)
gatt.subscribe(peer, handle)       # pass True as third argument for indications
event = gatt.poll(peer)           # call regularly from the application's loop
if event is not None:
    print(event["handle"], event["data"], event["indication"])
print(gatt.status(peer)["events_dropped"])
# When finished: gatt.unsubscribe(peer, handle)

Quick reference

Use solaros.ble for bluetooth. See man python for runtime conventions and service availability.

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