Wiki » History » Version 4
laforge, 08/22/2020 07:02 AM
1 | 1 | laforge | h1. Wiki |
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3 | 4 | laforge | {{>toc}} |
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5 | h2. Overview |
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7 | This wiki describes work within the Osmocom community to develop E1/T1 hardware interfaces. There were several different approaches taken, implemented to a verying degree and experimented with. |
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9 | If you are a user and not a developer, there are so far only two hardware interface projects that have reached the stage where they can be cnsidered ready/usable: |
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10 | * [[E1_tracer]] - a passive E1 tracer that can record the bi-directional bit-stream of an E1 line |
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11 | * [[ICE40 E1 USB interface]] - an inexpensive, open source hardware, gateware, firmware and software interface for terminating E1 circuits. |
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14 | h2. E1/T1 TDM technology |
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15 | 2 | laforge | |
16 | E1/T1 lines were pretty common in the 1990ies and up until about 2010, as they built the heart of many connections to the digital, circuit-switched telephony (ISDN) network. |
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18 | Today (2019), E1/T1 are mostly only found in connection with GSM base stations (BTS), where the Abis interface of a BTS is still officially only specified over E1/T1. |
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20 | Hardware for connecting E1/T1 to a (Linux) computer has always been expensive, and is rather difficult to find. Also, it only comes in PCI and PCIe form-factor, making it unsuitable to many popular embedded Linux platforms (whether ARM or x86) which don't feature such interfaces. |
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22 | We've been wokring on creating E1-USB adapters based on a variety of approaches, see further wiki pages for details. |
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24 | 1 | laforge | h2. Sub-pages |
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26 | {{child_pages}} |
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27 | 3 | laforge | |
28 | {{include(cellular-infrastructure:MacroCommercialSupport)}} |