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Keenetic Linear

The Keenetic Linear is a two-port FXS adapter with a USB interface. It allows you to interface two analog telephones with a soft switch or VoIP device. The vendor originally intends this device to be used with one of their own Router/CPE.

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Hardware

The hardware is based around the Skyworks Si32287 Single-chip Dual Channel ProSLIC attached to an EFM32HG310F64G (Cortex-M0+) microcontroller.

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USB interface

of course the vendor couldn't bother to implement a standard USB-Audio interface or similar. Instead, a custom CDC-ACM based interface is exposed by the device:

Bus 001 Device 124: ID 31b7:0002 Keenetic, Ltd. USB CDC serial port device
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            2 Communications
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  idVendor           0x31b7 
  idProduct          0x0002 
  bcdDevice            0.00
  iManufacturer           1 Keenetic, Ltd.
  iProduct                2 USB CDC serial port device
  iSerial                 3 S2145NS000558
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength       0x0043
    bNumInterfaces          2
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         2 Communications
      bInterfaceSubClass      2 Abstract (modem)
      bInterfaceProtocol      0 
      iInterface              0 
      CDC Header:
        bcdCDC               1.20
      CDC Call Management:
        bmCapabilities       0x00
        bDataInterface          1
      CDC ACM:
        bmCapabilities       0x02
          line coding and serial state
      CDC Union:
        bMasterInterface        0
        bSlaveInterface         1 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x82  EP 2 IN
        bmAttributes            3
          Transfer Type            Interrupt
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval             255
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass        10 CDC Data
      bInterfaceSubClass      0 
      bInterfaceProtocol      0 
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               0
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x01  EP 1 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0040  1x 64 bytes
        bInterval               0
Device Status:     0x0001
  Self Powered
Files (10)
Si3228x-datasheet.pdf View Si3228x-datasheet.pdf 1.16 MB laforge, 12/16/2022 11:54 AM
efm32hg-datasheet.pdf View efm32hg-datasheet.pdf 2.8 MB laforge, 12/16/2022 11:59 AM
20221216_125606.jpg View 20221216_125606.jpg 290 KB laforge, 12/16/2022 12:07 PM
20221216_125617.jpg View 20221216_125617.jpg 342 KB laforge, 12/16/2022 12:07 PM
20221216_125629.jpg View 20221216_125629.jpg 358 KB laforge, 12/16/2022 12:07 PM
20221216_130144.jpg View 20221216_130144.jpg 1010 KB laforge, 12/16/2022 12:08 PM
20221216_130152.jpg View 20221216_130152.jpg 953 KB laforge, 12/16/2022 12:08 PM
20221216_130317.jpg View 20221216_130317.jpg 735 KB laforge, 12/16/2022 12:08 PM
20221216_124809.jpg View 20221216_124809.jpg 1.75 MB laforge, 12/16/2022 12:09 PM
20221216_124803.jpg View 20221216_124803.jpg 1.74 MB laforge, 12/16/2022 12:09 PM

Updated by laforge over 1 year ago · 3 revisions

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