我正在尝试通过我的单板计算机实现 GSM 连接。我想我已经安排好了一切。以下是调制解调器信息的输出：
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General | dbus path: /org/freedesktop/ModemManager1/Modem/0
| device id: 10c51b4b5511adedf5c6df0380e7acab4ce64f5a
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Hardware | manufacturer: QUALCOMM INCORPORATED
| model: QUECTEL Mobile Broadband Module
| firmware revision: EC25AUFAR06A01M4G
| carrier config: default
| h/w revision: 10000
| supported: gsm-umts, lte
| current: gsm-umts, lte
| equipment id: 861585041067073
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System | device: /sys/devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2
| drivers: option1, qmi_wwan
| plugin: Quectel
| primary port: cdc-wdm0
| ports: ttyUSB0 (qcdm), ttyUSB2 (at), cdc-wdm0 (qmi), wwan0 (net),
| ttyUSB3 (at)
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Numbers | own: 61451690967
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Status | unlock retries: sim-pin (3), sim-pin2 (0), sim-puk (10), sim-puk2 (0)
| state: enabled
| power state: on
| signal quality: 0% (cached)
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Modes | supported: allowed: 2g; preferred: none
| allowed: 3g; preferred: none
| allowed: 4g; preferred: none
| allowed: 2g, 3g; preferred: 3g
| allowed: 2g, 3g; preferred: 2g
| allowed: 2g, 4g; preferred: 4g
| allowed: 2g, 4g; preferred: 2g
| allowed: 3g, 4g; preferred: 3g
| allowed: 3g, 4g; preferred: 4g
| allowed: 2g, 3g, 4g; preferred: 4g
| allowed: 2g, 3g, 4g; preferred: 3g
| allowed: 2g, 3g, 4g; preferred: 2g
| current: allowed: 2g, 3g, 4g; preferred: 4g
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Bands | supported: egsm, dcs, pcs, g850, utran-1, utran-5, utran-8, utran-2,
| eutran-1, eutran-2, eutran-3, eutran-4, eutran-5, eutran-7, eutran-8,
| eutran-28, eutran-40
| current: egsm, dcs, pcs, g850, utran-1, utran-5, utran-8, utran-2,
| eutran-1, eutran-2, eutran-3, eutran-4, eutran-5, eutran-7, eutran-8,
| eutran-28, eutran-40
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IP | supported: ipv4, ipv6, ipv4v6
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3GPP | imei: 861585041067073
| registration: idle
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3GPP EPS | ue mode of operation: csps-2
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SIM | dbus path: /org/freedesktop/ModemManager1/SIM/0
状态部分似乎没有显示信号。和输出nmcli con：
NAME UUID TYPE DEVICE
cellular d811a35a-70fc-3716-84e1-a3578d10cc1e gsm cdc-wdm0
resin-wifi-01 a58e405d-fdc2-3649-9339-5bbaea740c76 wifi wlan0
supervisor0 8148d985-dc90-4f8c-8e38-62f83f4f13ba bridge supervisor0
有线的事情是 GSM 总是连接（未连接过一次）：
cdc-wdm0: connecting (prepare) to cellular
"cdc-wdm0"
gsm (option1, qmi_wwan), hw
我尝试手动启动蜂窝网络：
root@6f5afca:~# nmcli c up cellular
Error: Connection activation failed: Network registration timed out
到目前为止，我已经尝试了一切。我用我的手机测试了 SIM 卡，它工作正常。我不知道为什么它没有连接。