{"id":21442232,"url":"https://github.com/thotypous/telecom-p2-board","last_synced_at":"2026-01-03T16:32:04.540Z","repository":{"id":251293108,"uuid":"836888201","full_name":"thotypous/telecom-p2-board","owner":"thotypous","description":"E1/T1 interface board for Tang Nano 9k","archived":false,"fork":false,"pushed_at":"2024-08-02T01:14:18.000Z","size":7037,"stargazers_count":0,"open_issues_count":0,"forks_count":0,"subscribers_count":1,"default_branch":"main","last_synced_at":"2025-01-23T10:43:26.255Z","etag":null,"topics":[],"latest_commit_sha":null,"homepage":"","language":null,"has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"mit","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/thotypous.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":"LICENSE","code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null}},"created_at":"2024-08-01T19:08:07.000Z","updated_at":"2024-08-02T01:24:57.000Z","dependencies_parsed_at":"2024-08-03T16:15:28.197Z","dependency_job_id":null,"html_url":"https://github.com/thotypous/telecom-p2-board","commit_stats":null,"previous_names":["thotypous/telecom-p2-board"],"tags_count":0,"template":false,"template_full_name":null,"repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/thotypous%2Ftelecom-p2-board","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/thotypous%2Ftelecom-p2-board/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/thotypous%2Ftelecom-p2-board/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/thotypous%2Ftelecom-p2-board/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/thotypous","download_url":"https://codeload.github.com/thotypous/telecom-p2-board/tar.gz/refs/heads/main","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":243955722,"owners_count":20374372,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2022-07-04T15:15:14.044Z","host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":[],"created_at":"2024-11-23T01:53:09.095Z","updated_at":"2026-01-03T16:32:04.510Z","avatar_url":"https://github.com/thotypous.png","language":null,"funding_links":[],"categories":[],"sub_categories":[],"readme":"# E1/T1 interface board for Tang Nano 9k\n\nThis is a simple adapter for connecting a FPGA board to an E1/T1 interface via short distance twisted pair.\n\nRX is done by a couple of comparators (KA319 or LM319) which detect, respectively, positive (`RXP_N` low) and negative (`RXN_N` low) pulses.\n\nTX is done directly by the FPGA pins. Current flows either from `TXP` to `TXN` to produce a positive pulse, or from `TXN` to `TXP` to produce a negative pulse.\n\nThe FPGA design is one of the exercises of the [Communications Technology class](https://telecom.matias.co.in) at [UFSCar](https://ufscar.br). Starter files and a guide for developing the project can be found [here](https://github.com/thotypous/telecom-p2).\n\n## Schematics\n\nSchematics are available both in [PDF](board/board.pdf) and in [Kicad format](board/board.kicad_sch).\n\n## PCB\n\nWe don't have a proper PCB layout. Please feel free to contribute one.\n\nInstead, please see below some photos of our milled by hand prototype board.\n\n![](photos/prototype01.jpg)\n\n![](photos/prototype02.jpg)\n\nPlease note that although one should ideally use 1:1 transformers, we only had at hand a couple of security camera baluns (designed to work as 75 ohm to 100 ohm impedance transformers), which worked just fine.\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fthotypous%2Ftelecom-p2-board","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fthotypous%2Ftelecom-p2-board","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fthotypous%2Ftelecom-p2-board/lists"}