{"id":20113800,"url":"https://github.com/mkj/pihelp","last_synced_at":"2025-06-13T11:37:54.700Z","repository":{"id":18148868,"uuid":"21242578","full_name":"mkj/pihelp","owner":"mkj","description":"A hardware watchdog for a Raspberry Pi using an AVR","archived":false,"fork":false,"pushed_at":"2017-02-27T15:09:52.000Z","size":1351,"stargazers_count":25,"open_issues_count":0,"forks_count":7,"subscribers_count":3,"default_branch":"master","last_synced_at":"2025-05-06T12:38:07.041Z","etag":null,"topics":[],"latest_commit_sha":null,"homepage":null,"language":"C","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":null,"status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/mkj.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":null,"license":null,"code_of_conduct":null,"threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null}},"created_at":"2014-06-26T14:01:10.000Z","updated_at":"2025-01-11T15:29:33.000Z","dependencies_parsed_at":"2022-09-05T17:41:22.832Z","dependency_job_id":null,"html_url":"https://github.com/mkj/pihelp","commit_stats":null,"previous_names":[],"tags_count":1,"template":false,"template_full_name":null,"purl":"pkg:github/mkj/pihelp","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mkj%2Fpihelp","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mkj%2Fpihelp/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mkj%2Fpihelp/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mkj%2Fpihelp/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/mkj","download_url":"https://codeload.github.com/mkj/pihelp/tar.gz/refs/heads/master","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/mkj%2Fpihelp/sbom","host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":259638703,"owners_count":22888496,"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":"2024-11-13T18:26:01.109Z","updated_at":"2025-06-13T11:37:54.678Z","avatar_url":"https://github.com/mkj.png","language":"C","funding_links":[],"categories":[],"sub_categories":[],"readme":"A hardware watchdog for a Raspberry Pi. It uses an atmega328 attached to the Raspberry Pi's\nserial port, with a simple command line interface.\n\nIt will reset the Raspberry Pi if either a long or short watchdog timer isn't reset within \na time period. It will also toggle a pin to alternate between booting to kernel\\_emergency.img\nand the normal kernel - see http://elinux.org/RPI_safe_mode . This makes it less risky to upgrading \nthe boot image remotely. There are a few other features such as a bodgy random number generator\nand hmac. The 'oneshot' watchdog lets you set a failsafe so that if you try something that doesn't work, it'l reboot after a set period of time.\n\nA rough list of functionality is in the [read handler](main.c#L1134).\n\nI implemented this to use with [PCextreme's](https://www.pcextreme.nl/) \n[Raspberry Colocation](http://raspberrycolocation.com/).\n\nThe system boots an initramfs as a bootloader with SSH - [Dropbear](https://github.com/mkj/dropbear) of course. I then boot the real kernel with [kexec](http://manpages.ubuntu.com/manpages/precise/man8/kexec.8.html) - that allows low-risk upgrades over the network.\n\n![schematic](pihelp.png)\n\n","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fmkj%2Fpihelp","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fmkj%2Fpihelp","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fmkj%2Fpihelp/lists"}