hcitool lescan
用于查看是否可以打开hci0设备。这导致了错误：
hcitool lescan Set scan parameters failed: Input/output error
此变通办法成功解决了该错误：
hciconfig hci0 down
hciconfig hci0 up
hcitool lescan
但是只有在'hcitool lescan'开始成功运行之后。尚不清楚我们是否必须真正捕获白名单中的已扫描设备才能使扫描成功完成（很快就赶上并停止了）。
在这些新的系统版本上，示例代码失败：
ii bluez 5.43-2+rpt2+deb9u2 armhf Bluetooth tools and daemons
ii bluez-firmware 1.2-3+rpt6 all Firmware for Bluetooth devices
ii bluez-hcidump 5.43-2+rpt2+deb9u2 armhf Analyses Bluetooth HCI packets
ii libbluetooth-dev 5.43-2+rpt2+deb9u2 armhf Development files for using the BlueZ Linux Bluetooth library
ii libbluetooth3:armhf 5.43-2+rpt2+deb9u2 armhf Library to use the BlueZ Linux Bluetooth stack
ii pi-bluetooth 0.1.8 all Raspberry Pi 3 bluetooth
ii python-bluez 0.22-1 armhf Python wrappers around BlueZ for rapid bluetooth development
但是可以在该系统上运行，请升级回一个版本：
ii bluez 5.43-2+rpt2+deb9u2 armhf Bluetooth tools and daemons
ii bluez-firmware 1.2-3+rpt5 all Firmware for Bluetooth devices
ii libbluetooth-dev 5.43-2+rpt2+deb9u2 armhf Development files for using the BlueZ Linux Bluetooth library
ii libbluetooth3:armhf 5.43-2+rpt2+deb9u2 armhf Library to use the BlueZ Linux Bluetooth stack
ii pi-bluetooth 0.1.7 all Raspberry Pi 3 bluetooth
ii python-bluez 0.22-1 armhf Python wrappers around BlueZ for rapid bluetooth development
编辑：btmon命令的输出（新的无效单元）：
Bluetooth monitor ver 5.43
= Note: Linux version 4.14.52-v7+ (armv7l) 0.695265
= Note: Bluetooth subsystem version 2.22 0.695276
= New Index: B8:27:EB:A0:39:EC (Primary,UART,hci0) [hci0] 0.695279
= Open Index: B8:27:EB:A0:39:EC [hci0] 0.695281
= Index Info: B8:27:EB:A0:39:EC (Broadcom Corporation) [hci0] 0.695284
@ RAW Open: python (privileged) version 2.22 {0x0003} [hci0] 0.695289
@ RAW Open: hcitool (privileged) version 2.22 {0x0002} [hci0] 0.695291
@ MGMT Open: bluetoothd (privileged) version 1.14 {0x0001} 0.695294
@ MGMT Open: btmon (privileged) version 1.14 {0x0004} 0.695367
> HCI Event: LE Meta Event (0x3e) plen 40 [hci0] 2.692582
LE Advertising Report (0x02)
Num reports: 1
Event type: Scannable undirected - ADV_SCAN_IND (0x02)
Address type: Random (0x01)
Address: 51:46:AD:CA:4C:2F (Resolvable)
Data length: 28
16-bit Service UUIDs (complete): 1 entry
Google (0xfe9f)
Service Data (UUID 0xfe9f): 0000000000000000000000000000000000000000
RSSI: -84 dBm (0xac)
较旧的工作单位：
Bluetooth monitor ver 5.43
= Note: Linux version 4.14.34-v7+ (armv7l) 0.396738
= Note: Bluetooth subsystem version 2.22 0.396744
= New Index: B8:27:EB:31:E6:62 (Primary,UART,hci0) [hci0] 0.396746
= Open Index: B8:27:EB:31:E6:62 [hci0] 0.396748
= Index Info: B8:27:EB:31:E6:62 (Broadcom Corporation) [hci0] 0.396749
@ RAW Open: python (privileged) version 2.22 {0x0002} [hci0] 0.396752
@ MGMT Open: bluetoothd (privileged) version 1.14 {0x0001} 0.396753
@ MGMT Open: btmon (privileged) version 1.14 {0x0003} 0.396800
> HCI Event: LE Meta Event (0x3e) plen 42 [hci0] 0.534168
LE Advertising Report (0x02)
Num reports: 1
Event type: Non connectable undirected - ADV_NONCONN_IND (0x03)
Address type: Public (0x00)
Address: 0C:F3:EE:B3:B8:53 (EM Microelectronic)
Data length: 30
Flags: 0x06
LE General Discoverable Mode
BR/EDR Not Supported
Company: Apple, Inc. (76)
Type: iBeacon (2)
UUID: a6ffa91b-91f4-f2ad-0f4a-6dcf5444232f
Version: 0.256
TX power: -76 dB
RSSI: -70 dBm (0xba)
答案 0 :(得分：1)
因此，您的扫描似乎已经处于活动状态（因为它发送了广告包）？ lescan命令首先设置扫描参数，然后开始扫描。如果已经在进行扫描，则HCI禁止使用set scan parameters命令。
答案 1 :(得分：0)
答案 2 :(得分：0)
start C:\\MyTemplate.dotx
#!/bin/sh
sudo hciconfig hci0 down
sudo hciconfig hci0 up
sudo timeout -s INT 1s hcitool lescan
cd /
cd home/pi/proPi/
sudo timeout -s INT 1s python *detectAll.py* (replace with your Phyton script name)
cd /
并添加以下内容：sudo crontab -e