Beanfield · Jul to Nov 2026
TV wall and wall bot
A wall of 8 screens shows 72 live channels at once, so a reported outage is confirmed against the real picture in seconds. I mapped the controller, built a Webex bot that changes the wall in plain words, made the reset safe, and put a live view of the wall into the monitoring GUI.
The problem
The wall was driven through the vendor's controller portal, one tile at a time by hand. The old bot needed exact commands such as wall panel 3 606. On 16 Aug 2026 the CTO asked for plain commands.
What I did
- Documented the wall end to end: source, transport, lab, controller and the 8 displays, in one script-built diagram.
- Mapped the controller: one server with five GPUs, 8 panels by 9 tiles = 72 tiles, decoding pinned two panels per GPU; channel list of 193 rows.
- Chose the 72 channels on purpose: the most-ticketed channels, the biggest audiences, complaint-sensitive sports and the French channels carried under CRTC rules.
- Built a Webex bot: status, help, channel list, set one panel, hero channel, five themes (news 16, sports 18, movies 20, lifestyle 19, french 19 channels) in small or medium layouts, and reset.
- Made every wall write go through a named function: snapshot, write, restart, verify. Reset back to normal applies and verifies in 38 seconds, all 8 panels active.
- Fixed a silent failure: the old bot container looked up while 97% of its polls (53,670 of 55,241) failed. That led to the rule "running is not working".
- 3 Nov 2026: one channel shown as a single picture across all 8 panels, and a Wall View page in the monitoring GUI with a live picture every 15 s and a 3-minute live video on request.
- Made remote access to the controller dependable, with self-healing every 5 minutes. Published the bot guide and the setup guide as knowledge articles.
Plain-word commands, a design decision
Two options: a language model to read commands, or a smarter rule-based reader. I chose the rule-based reader: no outside calls, testable offline, no extra security review. It accepts "put tsn 4 on monitor 3", "cp24 on 1, cnn on 2 and bbc world on 3" and place names such as "top left", never guesses, and offers a "did you mean" list. Built, tested offline and deployed on 23 Sep 2026; live check passed the same afternoon.
What was hard
- Display numbers do not follow wall order (top row 5, 2, 3, 4; bottom row 1, 6, 7, 8).
- A 4 by 4 rebuild was blocked, so the wall stays at 72 tiles.
- Four satellite channels share one receiver on a different port.