本文章介紹在Raspberry Pi Pico W上使用tinyusb HID host與BTstack HID device將有線的USB keyboard轉成Bluetooth無線的keyborad。在desktop PC與cell phone上測試藍芽無線鍵盤輸入。
參考文件：
- Device Class Definition for Human Interface Devices (HID)
- HID Usage Tables FOR Universal Serial Bus (USB)
- HUMAN INTERFACE DEVICE PROFILE 1.1
- https://usb.org/
根據文件說明，由HID device輸入字後轉成HID input report輸出。
HID host 再將HID input report轉成字元輸出。
鍵盤輸入字元時，產生HID input report到Pico W usb host port。再將HID input report透過 Pico W bluetooth HID device輸出到 PC or cell phone HID host。
HID input report主要有8 bytes: {modifier, 0, keycode1, keycode2, keycode3, keycode4, keycode5, keycode6}。以wireshark擷取封包，如下圖所示。
測試結果請參閱下列成果影片。
程式碼主要修改於tinyusb hid_app.c example與btstack hid_keyboard_demo.c。詳細程式碼請參閱文末說明，動態說明請參閱成果影片。
成果影片：
程式碼：
- pico_bt_hid_keyboard.c
#include <stdio.h> #include "pico/stdlib.h" #include "bsp/board.h" #include "tusb.h" #include "pico/cyw43_arch.h" #include "pico/util/queue.h" queue_t hid_keyboard_report_queue; extern void btstack_hid_kb_init(); int main() { stdio_init_all(); if (cyw43_arch_init()) { printf("cyw43_init_error\n"); return 0; } btstack_hid_kb_init(); queue_init_with_spinlock(&hid_keyboard_report_queue, sizeof(hid_keyboard_report_t), 10, spin_lock_claim_unused(true)); board_init(); if (!tuh_init(BOARD_TUH_RHPORT)) { printf("tuh init\n"); return 0; } else { printf("tinyusb init successfully\n"); } while(1) { // tinyusb host task tuh_task(); } return 0; }
- hid_app.c -- 只有修改rocess_kbd_report function(tusb_hid.c)
static void process_kbd_report(hid_keyboard_report_t const *report) { queue_try_add(&hid_keyboard_report_queue, report); return; }
- btstack_hid_kb.c
/* This file was modified from btstack hid_keyboard_demo.c example*/ /* * Copyright (C) 2014 BlueKitchen GmbH * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the copyright holders nor the names of * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * 4. Any redistribution, use, or modification is done solely for * personal benefit and not for any commercial purpose or for * monetary gain. * * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * Please inquire about commercial licensing options at * contact@bluekitchen-gmbh.com * */ // ***************************************************************************** /* EXAMPLE_START(hid_keyboard_demo): HID Keyboard Classic * * @text This HID Device example demonstrates how to implement * an HID keyboard. Without a HAVE_BTSTACK_STDIN, a fixed demo text is sent * If HAVE_BTSTACK_STDIN is defined, you can type from the terminal */ // ***************************************************************************** #include <stdint.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <inttypes.h> #include "btstack.h" #include "pico/util/queue.h" extern queue_t hid_keyboard_report_queue; // When not set to 0xffff, sniff and sniff subrating are enabled static uint16_t host_max_latency = 1600; static uint16_t host_min_timeout = 3200; #define REPORT_ID 0x01 // close to USB HID Specification 1.1, Appendix B.1 const uint8_t hid_descriptor_keyboard[] = { 0x05, 0x01, // Usage Page (Generic Desktop) 0x09, 0x06, // Usage (Keyboard) 0xa1, 0x01, // Collection (Application) // Report ID 0x85, REPORT_ID, // Report ID // Modifier byte (input) 0x05, 0x07, // Usage Page (Key Codes) 0x75, 0x01, // Report Size (1) 0x95, 0x08, // Report Count (8) 0x05, 0x07, // Usage Page (Key codes) 0x19, 0xe0, // Usage Minimum (Keyboard LeftControl) 0x29, 0xe7, // Usage Maxium (Keyboard Right GUI) 0x15, 0x00, // Logical Minimum (0) 0x25, 0x01, // Logical Maximum (1) 0x81, 0x02, // Input (Data, Variable, Absolute) // Reserved byte (input) 0x75, 0x01, // Report Size (1) 0x95, 0x08, // Report Count (8) 0x81, 0x03, // Input (Constant, Variable, Absolute) // LED report + padding (output) 0x95, 0x05, // Report Count (5) 0x75, 0x01, // Report Size (1) 0x05, 0x08, // Usage Page (LEDs) 0x19, 0x01, // Usage Minimum (Num Lock) 0x29, 0x05, // Usage Maxium (Kana) 0x91, 0x02, // Output (Data, Variable, Absolute) 0x95, 0x01, // Report Count (1) 0x75, 0x03, // Report Size (3) 0x91, 0x03, // Output (Constant, Variable, Absolute) // Keycodes (input) 0x95, 0x06, // Report Count (6) 0x75, 0x08, // Report Size (8) 0x15, 0x00, // Logical Minimum (0) 0x25, 0xff, // Logical Maximum (1) 0x05, 0x07, // Usage Page (Key codes) 0x19, 0x00, // Usage Minimum (Reserved (no event indicated)) 0x29, 0xff, // Usage Maxium (Reserved) 0x81, 0x00, // Input (Data, Array) 0xc0, // End collection }; // STATE static uint8_t hid_service_buffer[300]; static uint8_t device_id_sdp_service_buffer[100]; static const char hid_device_name[] = "BTstack HID Keyboard"; static btstack_packet_callback_registration_t hci_event_callback_registration; static uint16_t hid_cid; static uint8_t hid_boot_device = 0; // HID Report sending static uint8_t send_modifier; static uint8_t send_keycode; static enum { APP_BOOTING, APP_NOT_CONNECTED, APP_CONNECTING, APP_CONNECTED } app_state = APP_BOOTING; //=======Code Modified Begin================= static void send_report(int modifier, int keycode){ uint8_t report[] = { 0xa1, REPORT_ID, modifier, 0, keycode, 0, 0, 0, 0, 0}; hid_device_send_interrupt_message(hid_cid, &report[0], sizeof(report)); } #define TEXT_PERIOD_MS 20 static btstack_timer_source_t text_timer; static void text_timer_handler(btstack_timer_source_t * ts){ struct { uint8_t modifier; /**< Keyboard modifier (KEYBOARD_MODIFIER_* masks). */ uint8_t reserved; /**< Reserved for OEM use, always set to 0. */ uint8_t keycode[6]; /**< Key codes of the currently pressed keys. */ } report_q; if (queue_try_remove(&hid_keyboard_report_queue, &report_q)) { uint8_t report[] = { 0xa1, REPORT_ID, report_q.modifier, 0, report_q.keycode[0],report_q.keycode[1],report_q.keycode[2],report_q.keycode[3],report_q.keycode[4],report_q.keycode[5]}; hid_device_send_interrupt_message(hid_cid, &report[0], sizeof(report)); } hid_device_request_can_send_now_event(hid_cid); } //=======Code Modified End=============== static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t * packet, uint16_t packet_size){ UNUSED(channel); UNUSED(packet_size); uint8_t status; switch (packet_type){ case HCI_EVENT_PACKET: switch (hci_event_packet_get_type(packet)){ case BTSTACK_EVENT_STATE: if (btstack_event_state_get_state(packet) != HCI_STATE_WORKING) return; app_state = APP_NOT_CONNECTED; break; case HCI_EVENT_USER_CONFIRMATION_REQUEST: // ssp: inform about user confirmation request log_info("SSP User Confirmation Request with numeric value '%06"PRIu32"'\n", hci_event_user_confirmation_request_get_numeric_value(packet)); log_info("SSP User Confirmation Auto accept\n"); break; case HCI_EVENT_HID_META: switch (hci_event_hid_meta_get_subevent_code(packet)){ case HID_SUBEVENT_CONNECTION_OPENED: status = hid_subevent_connection_opened_get_status(packet); if (status != ERROR_CODE_SUCCESS) { // outgoing connection failed printf("Connection failed, status 0x%x\n", status); app_state = APP_NOT_CONNECTED; hid_cid = 0; return; } app_state = APP_CONNECTED; hid_cid = hid_subevent_connection_opened_get_hid_cid(packet); btstack_run_loop_set_timer_handler(&text_timer, text_timer_handler); btstack_run_loop_set_timer(&text_timer, TEXT_PERIOD_MS); btstack_run_loop_add_timer(&text_timer); break; case HID_SUBEVENT_CONNECTION_CLOSED: printf("HID Disconnected\n"); app_state = APP_NOT_CONNECTED; hid_cid = 0; break; case HID_SUBEVENT_CAN_SEND_NOW: //send_report(send_modifier, send_keycode); btstack_run_loop_set_timer_handler(&text_timer, text_timer_handler); btstack_run_loop_set_timer(&text_timer, TEXT_PERIOD_MS); btstack_run_loop_add_timer(&text_timer); break; default: break; } break; default: break; } break; default: break; } } void btstack_hid_kb_init() { // allow to get found by inquiry gap_discoverable_control(1); // use Limited Discoverable Mode; Peripheral; Keyboard as CoD gap_set_class_of_device(0x2540); // allow for role switch in general and sniff mode gap_set_default_link_policy_settings( LM_LINK_POLICY_ENABLE_ROLE_SWITCH | LM_LINK_POLICY_ENABLE_SNIFF_MODE ); // allow for role switch on outgoing connections - this allow HID Host to become master when we re-connect to it gap_set_allow_role_switch(true); gap_set_local_name(hid_device_name); // L2CAP l2cap_init(); // SDP Server sdp_init(); memset(hid_service_buffer, 0, sizeof(hid_service_buffer)); uint8_t hid_virtual_cable = 0; uint8_t hid_remote_wake = 1; uint8_t hid_reconnect_initiate = 1; uint8_t hid_normally_connectable = 1; hid_sdp_record_t hid_params = { // hid sevice subclass 2540 Keyboard, hid counntry code 33 US 0x2540, 33, hid_virtual_cable, hid_remote_wake, hid_reconnect_initiate, hid_normally_connectable, hid_boot_device, host_max_latency, host_min_timeout, 3200, hid_descriptor_keyboard, sizeof(hid_descriptor_keyboard), hid_device_name }; hid_create_sdp_record(hid_service_buffer, 0x10001, &hid_params); printf("HID service record size: %u\n", de_get_len( hid_service_buffer)); sdp_register_service(hid_service_buffer); // See https://www.bluetooth.com/specifications/assigned-numbers/company-identifiers if you don't have a USB Vendor ID and need a Bluetooth Vendor ID // device info: BlueKitchen GmbH, product 1, version 1 device_id_create_sdp_record(device_id_sdp_service_buffer, 0x10003, DEVICE_ID_VENDOR_ID_SOURCE_BLUETOOTH, BLUETOOTH_COMPANY_ID_BLUEKITCHEN_GMBH, 1, 1); printf("Device ID SDP service record size: %u\n", de_get_len((uint8_t*)device_id_sdp_service_buffer)); sdp_register_service(device_id_sdp_service_buffer); // HID Device hid_device_init(hid_boot_device, sizeof(hid_descriptor_keyboard), hid_descriptor_keyboard); // register for HCI events hci_event_callback_registration.callback = &packet_handler; hci_add_event_handler(&hci_event_callback_registration); // register for HID events hid_device_register_packet_handler(&packet_handler); // turn on! hci_power_control(HCI_POWER_ON); } /* LISTING_END */ /* EXAMPLE_END */
- CMakeLists.txt
# Generated Cmake Pico project file cmake_minimum_required(VERSION 3.13) set(CMAKE_C_STANDARD 11) set(CMAKE_CXX_STANDARD 17) # Initialise pico_sdk from installed location # (note this can come from environment, CMake cache etc) set(PICO_SDK_PATH "/home/duser/pico/pico-sdk") set(PICO_BOARD pico_w CACHE STRING "Board type") # Pull in Raspberry Pi Pico SDK (must be before project) include(pico_sdk_import.cmake) if (PICO_SDK_VERSION_STRING VERSION_LESS "1.4.0") message(FATAL_ERROR "Raspberry Pi Pico SDK version 1.4.0 (or later) required. Your version is ${PICO_SDK_VERSION_STRING}") endif() project(picow_bt_hid_keyboard C CXX ASM) # Initialise the Raspberry Pi Pico SDK pico_sdk_init() # Add executable. Default name is the project name, version 0.1 add_executable(picow_bt_hid_keyboard picow_bt_hid_keyboard.c tusb_hid.c btstack_hid_kb.c) pico_set_program_name(picow_bt_hid_keyboard "picow_bt_hid_keyboard") pico_set_program_version(picow_bt_hid_keyboard "0.1") pico_enable_stdio_uart(picow_bt_hid_keyboard 1) pico_enable_stdio_usb(picow_bt_hid_keyboard 0) # Add the standard library to the build target_link_libraries(picow_bt_hid_keyboard pico_stdlib pico_util pico_cyw43_arch_none pico_btstack_cyw43 pico_btstack_classic) # Add the standard include files to the build target_include_directories(picow_bt_hid_keyboard PRIVATE ${CMAKE_CURRENT_LIST_DIR} ${CMAKE_CURRENT_LIST_DIR}/.. # for our common lwipopts or any other standard includes, if required ) # Add any user requested libraries ---------- target_link_libraries(picow_bt_hid_keyboard tinyusb_host tinyusb_board ) pico_add_extra_outputs(picow_bt_hid_keyboard)
